From 130e0ea5f02ba6d6238b530fdee90fb0c36462a5 Mon Sep 17 00:00:00 2001
From: Haleygo <hui.wang@daocloud.io>
Date: Fri, 13 Oct 2023 19:54:33 +0800
Subject: [PATCH] vmalert-tool: implement unittest (#4789)

1. split package rule under /app/vmalert, expose needed objects
2. add vmalert-tool with unittest subcmd

https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2945
---
 Makefile                                      |   1 +
 app/vmalert-tool/Makefile                     | 103 ++++
 app/vmalert-tool/README.md                    | 244 ++++++++++
 app/vmalert-tool/main.go                      |  54 +++
 app/vmalert-tool/unittest/alerting.go         |  19 +
 app/vmalert-tool/unittest/input.go            | 182 +++++++
 app/vmalert-tool/unittest/input_test.go       |  93 ++++
 app/vmalert-tool/unittest/recording.go        |  92 ++++
 .../testdata/disable-group-label.yaml         |  43 ++
 .../unittest/testdata/failed-test.yaml        |  49 ++
 .../unittest/testdata/long-period.yaml        |  30 ++
 app/vmalert-tool/unittest/testdata/rules.yaml |  39 ++
 app/vmalert-tool/unittest/testdata/test1.yaml |  99 ++++
 app/vmalert-tool/unittest/testdata/test2.yaml |  46 ++
 app/vmalert-tool/unittest/type.go             |  83 ++++
 app/vmalert-tool/unittest/unittest.go         | 443 ++++++++++++++++++
 app/vmalert-tool/unittest/unittest_test.go    |  47 ++
 app/vmalert/README.md                         |   5 +
 app/vmalert/datasource/faker.go               | 131 ++++++
 app/vmalert/main.go                           |  12 +-
 app/vmalert/main_test.go                      |  14 +-
 app/vmalert/manager.go                        | 117 +----
 app/vmalert/manager_test.go                   | 101 ++--
 app/vmalert/notifier/faker.go                 |  59 +++
 app/vmalert/remotewrite/client.go             | 322 +++++++++++++
 .../{remotewrite_test.go => client_test.go}   |   0
 app/vmalert/remotewrite/debug_client.go       |  97 ++++
 app/vmalert/remotewrite/debug_client_test.go  |  50 ++
 app/vmalert/remotewrite/remotewrite.go        | 321 +------------
 app/vmalert/replay.go                         | 107 +----
 app/vmalert/replay_test.go                    |  80 +---
 app/vmalert/rule.go                           | 118 -----
 app/vmalert/{ => rule}/alerting.go            | 236 ++++------
 app/vmalert/{ => rule}/alerting_test.go       |  82 ++--
 app/vmalert/{ => rule}/group.go               | 215 +++++++--
 app/vmalert/{ => rule}/group_test.go          | 206 ++++++--
 app/vmalert/{ => rule}/recording.go           |  91 ++--
 app/vmalert/{ => rule}/recording_test.go      |  52 +-
 app/vmalert/rule/rule.go                      | 174 +++++++
 app/vmalert/rule/rule_test.go                 |  81 ++++
 .../{helpers_test.go => rule/test_helpers.go} | 271 ++---------
 app/vmalert/{ => rule}/utils.go               |   2 +-
 app/vmalert/{ => rule}/utils_test.go          |   2 +-
 app/vmalert/rule_test.go                      | 100 ----
 app/vmalert/web.go                            |  67 ++-
 app/vmalert/web.qtpl                          |  42 +-
 app/vmalert/web.qtpl.go                       |  64 +--
 app/vmalert/web_test.go                       |  54 +--
 app/vmalert/web_types.go                      | 242 +++++++++-
 app/vmalert/web_types_test.go                 |  23 +
 docs/Articles.md                              |   8 +-
 docs/BestPractices.md                         |   8 +-
 docs/CHANGELOG.md                             |  10 +-
 docs/CHANGELOG_2020.md                        |   8 +-
 docs/CHANGELOG_2021.md                        |   8 +-
 docs/CHANGELOG_2022.md                        |   8 +-
 docs/CaseStudies.md                           |   8 +-
 docs/FAQ.md                                   |   8 +-
 docs/MetricsQL.md                             |   8 +-
 docs/PerTenantStatistic.md                    |   8 +-
 docs/Quick-Start.md                           |   8 +-
 docs/Release-Guide.md                         |   8 +-
 docs/Troubleshooting.md                       |   8 +-
 docs/enterprise.md                            |   2 +-
 docs/keyConcepts.md                           |   8 +-
 docs/relabeling.md                            |   8 +-
 docs/sd_configs.md                            |   8 +-
 docs/stream-aggregation.md                    |   2 +-
 docs/url-examples.md                          |   8 +-
 docs/vmalert-tool.md                          | 253 ++++++++++
 docs/vmalert.md                               |   5 +
 docs/vmanomaly.md                             |   2 +-
 lib/promutils/duration.go                     |   8 +
 73 files changed, 3952 insertions(+), 1663 deletions(-)
 create mode 100644 app/vmalert-tool/Makefile
 create mode 100644 app/vmalert-tool/README.md
 create mode 100644 app/vmalert-tool/main.go
 create mode 100644 app/vmalert-tool/unittest/alerting.go
 create mode 100644 app/vmalert-tool/unittest/input.go
 create mode 100644 app/vmalert-tool/unittest/input_test.go
 create mode 100644 app/vmalert-tool/unittest/recording.go
 create mode 100644 app/vmalert-tool/unittest/testdata/disable-group-label.yaml
 create mode 100644 app/vmalert-tool/unittest/testdata/failed-test.yaml
 create mode 100644 app/vmalert-tool/unittest/testdata/long-period.yaml
 create mode 100644 app/vmalert-tool/unittest/testdata/rules.yaml
 create mode 100644 app/vmalert-tool/unittest/testdata/test1.yaml
 create mode 100644 app/vmalert-tool/unittest/testdata/test2.yaml
 create mode 100644 app/vmalert-tool/unittest/type.go
 create mode 100644 app/vmalert-tool/unittest/unittest.go
 create mode 100644 app/vmalert-tool/unittest/unittest_test.go
 create mode 100644 app/vmalert/datasource/faker.go
 create mode 100644 app/vmalert/notifier/faker.go
 create mode 100644 app/vmalert/remotewrite/client.go
 rename app/vmalert/remotewrite/{remotewrite_test.go => client_test.go} (100%)
 create mode 100644 app/vmalert/remotewrite/debug_client.go
 create mode 100644 app/vmalert/remotewrite/debug_client_test.go
 delete mode 100644 app/vmalert/rule.go
 rename app/vmalert/{ => rule}/alerting.go (81%)
 rename app/vmalert/{ => rule}/alerting_test.go (94%)
 rename app/vmalert/{ => rule}/group.go (73%)
 rename app/vmalert/{ => rule}/group_test.go (74%)
 rename app/vmalert/{ => rule}/recording.go (68%)
 rename app/vmalert/{ => rule}/recording_test.go (86%)
 create mode 100644 app/vmalert/rule/rule.go
 create mode 100644 app/vmalert/rule/rule_test.go
 rename app/vmalert/{helpers_test.go => rule/test_helpers.go} (54%)
 rename app/vmalert/{ => rule}/utils.go (99%)
 rename app/vmalert/{ => rule}/utils_test.go (99%)
 delete mode 100644 app/vmalert/rule_test.go
 create mode 100644 app/vmalert/web_types_test.go
 create mode 100644 docs/vmalert-tool.md

diff --git a/Makefile b/Makefile
index 407525a26..75b338083 100644
--- a/Makefile
+++ b/Makefile
@@ -276,3 +276,4 @@ docs-sync:
 	SRC=app/vmctl/README.md DST=docs/vmctl.md OLD_URL='/vmctl.html' ORDER=8 TITLE=vmctl $(MAKE) copy-docs
 	SRC=app/vmgateway/README.md DST=docs/vmgateway.md OLD_URL='/vmgateway.html' ORDER=9 TITLE=vmgateway $(MAKE) copy-docs
 	SRC=app/vmbackupmanager/README.md DST=docs/vmbackupmanager.md OLD_URL='/vmbackupmanager.html' ORDER=10 TITLE=vmbackupmanager $(MAKE) copy-docs
+	SRC=app/vmalert-tool/README.md DST=docs/vmalert-tool.md OLD_URL='' ORDER=12 TITLE=vmalert-tool $(MAKE) copy-docs
diff --git a/app/vmalert-tool/Makefile b/app/vmalert-tool/Makefile
new file mode 100644
index 000000000..dbb6b373a
--- /dev/null
+++ b/app/vmalert-tool/Makefile
@@ -0,0 +1,103 @@
+# All these commands must run from repository root.
+
+vmalert-tool:
+	APP_NAME=vmalert-tool $(MAKE) app-local
+
+vmalert-tool-race:
+	APP_NAME=vmalert-tool RACE=-race $(MAKE) app-local
+
+vmalert-tool-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker
+
+vmalert-tool-pure-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-pure
+
+vmalert-tool-linux-amd64-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-linux-amd64
+
+vmalert-tool-linux-arm-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-linux-arm
+
+vmalert-tool-linux-arm64-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-linux-arm64
+
+vmalert-tool-linux-ppc64le-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-linux-ppc64le
+
+vmalert-tool-linux-386-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-linux-386
+
+vmalert-tool-darwin-amd64-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-darwin-amd64
+
+vmalert-tool-darwin-arm64-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-darwin-arm64
+
+vmalert-tool-freebsd-amd64-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-freebsd-amd64
+
+vmalert-tool-openbsd-amd64-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-openbsd-amd64
+
+vmalert-tool-windows-amd64-prod:
+	APP_NAME=vmalert-tool $(MAKE) app-via-docker-windows-amd64
+
+package-vmalert-tool:
+	APP_NAME=vmalert-tool $(MAKE) package-via-docker
+
+package-vmalert-tool-pure:
+	APP_NAME=vmalert-tool $(MAKE) package-via-docker-pure
+
+package-vmalert-tool-amd64:
+	APP_NAME=vmalert-tool $(MAKE) package-via-docker-amd64
+
+package-vmalert-tool-arm:
+	APP_NAME=vmalert-tool $(MAKE) package-via-docker-arm
+
+package-vmalert-tool-arm64:
+	APP_NAME=vmalert-tool $(MAKE) package-via-docker-arm64
+
+package-vmalert-tool-ppc64le:
+	APP_NAME=vmalert-tool $(MAKE) package-via-docker-ppc64le
+
+package-vmalert-tool-386:
+	APP_NAME=vmalert-tool $(MAKE) package-via-docker-386
+
+publish-vmalert-tool:
+	APP_NAME=vmalert-tool $(MAKE) publish-via-docker
+
+vmalert-tool-linux-amd64:
+	APP_NAME=vmalert-tool CGO_ENABLED=1 GOOS=linux GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+vmalert-tool-linux-arm:
+	APP_NAME=vmalert-tool CGO_ENABLED=0 GOOS=linux GOARCH=arm $(MAKE) app-local-goos-goarch
+
+vmalert-tool-linux-arm64:
+	APP_NAME=vmalert-tool CGO_ENABLED=0 GOOS=linux GOARCH=arm64 $(MAKE) app-local-goos-goarch
+
+vmalert-tool-linux-ppc64le:
+	APP_NAME=vmalert-tool CGO_ENABLED=0 GOOS=linux GOARCH=ppc64le $(MAKE) app-local-goos-goarch
+
+vmalert-tool-linux-s390x:
+	APP_NAME=vmalert-tool CGO_ENABLED=0 GOOS=linux GOARCH=s390x $(MAKE) app-local-goos-goarch
+
+vmalert-tool-linux-386:
+	APP_NAME=vmalert-tool CGO_ENABLED=0 GOOS=linux GOARCH=386 $(MAKE) app-local-goos-goarch
+
+vmalert-tool-darwin-amd64:
+	APP_NAME=vmalert-tool CGO_ENABLED=0 GOOS=darwin GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+vmalert-tool-darwin-arm64:
+	APP_NAME=vmalert-tool CGO_ENABLED=0 GOOS=darwin GOARCH=arm64 $(MAKE) app-local-goos-goarch
+
+vmalert-tool-freebsd-amd64:
+	APP_NAME=vmalert-tool CGO_ENABLED=0 GOOS=freebsd GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+vmalert-tool-openbsd-amd64:
+	APP_NAME=vmalert-tool CGO_ENABLED=0 GOOS=openbsd GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+vmalert-tool-windows-amd64:
+	GOARCH=amd64 APP_NAME=vmalert-tool $(MAKE) app-local-windows-goarch
+
+vmalert-tool-pure:
+	APP_NAME=vmalert-tool $(MAKE) app-local-pure
diff --git a/app/vmalert-tool/README.md b/app/vmalert-tool/README.md
new file mode 100644
index 000000000..e25465275
--- /dev/null
+++ b/app/vmalert-tool/README.md
@@ -0,0 +1,244 @@
+
+# vmalert-tool
+
+VMAlert command-line tool
+
+## Unit testing for rules
+
+You can use `vmalert-tool` to run unit tests for alerting and recording rules.
+It will perform the following actions:
+* sets up an isolated VictoriaMetrics instance;
+* simulates the periodic ingestion of time series;
+* queries the ingested data for recording and alerting rules evaluation like [vmalert](https://docs.victoriametrics.com/vmalert.html);
+* checks whether the firing alerts or resulting recording rules match the expected results.
+
+See how to run vmalert-tool for unit test below:
+```
+# Run vmalert-tool with one or multiple test files via --files cmd-line flag
+./vmalert-tool unittest --files test1.yaml --files test2.yaml
+```
+
+vmalert-tool unittest is compatible with [Prometheus config format for tests](https://prometheus.io/docs/prometheus/latest/configuration/unit_testing_rules/#test-file-format)
+except `promql_expr_test` field. Use `metricsql_expr_test` field name instead. The name is different because vmalert-tool
+validates and executes [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html) expressions,
+which aren't always backward compatible with [PromQL](https://prometheus.io/docs/prometheus/latest/querying/basics/).
+
+### Test file format
+
+The configuration format for files specified in `--files` cmd-line flag is the following:
+```
+# Path to the files or http url containing [rule groups](https://docs.victoriametrics.com/vmalert.html#groups) configuration.
+# Enterprise version of vmalert-tool supports S3 and GCS paths to rules.
+rule_files:
+  [ - <string> ]
+
+# The evaluation interval for rules specified in `rule_files`
+[ evaluation_interval: <duration> | default = 1m ]
+
+# Groups listed below will be evaluated by order.
+# Not All the groups need not be mentioned, if not, they will be evaluated by define order in rule_files.
+group_eval_order:
+  [ - <string> ]
+
+# The list of unit test files to be checked during evaluation.
+tests:
+  [ - <test_group> ]
+```
+
+#### `<test_group>`
+
+```
+# Interval between samples for input series
+interval: <duration>
+# Time series to persist into the database according to configured <interval> before running tests.
+input_series:
+  [ - <series> ]
+
+# Name of the test group, optional
+[ name: <string> ]
+
+# Unit tests for alerting rules
+alert_rule_test:
+  [ - <alert_test_case> ]
+
+# Unit tests for Metricsql expressions.
+metricsql_expr_test:
+  [ - <metricsql_expr_test> ]
+
+# External labels accessible for templating.
+external_labels:
+  [ <labelname>: <string> ... ]
+
+```
+
+#### `<series>`
+
+```
+# series in the following format '<metric name>{<label name>=<label value>, ...}'
+# Examples:
+#      series_name{label1="value1", label2="value2"}
+#      go_goroutines{job="prometheus", instance="localhost:9090"}
+series: <string>
+
+# values support several special equations:
+#    'a+bxc' becomes 'a a+b a+(2*b) a+(3*b) … a+(c*b)'
+#     Read this as series starts at a, then c further samples incrementing by b.
+#    'a-bxc' becomes 'a a-b a-(2*b) a-(3*b) … a-(c*b)'
+#     Read this as series starts at a, then c further samples decrementing by b (or incrementing by negative b).
+#    '_' represents a missing sample from scrape
+#    'stale' indicates a stale sample
+# Examples:
+#     1. '-2+4x3' becomes '-2 2 6 10' - series starts at -2, then 3 further samples incrementing by 4.
+#     2. ' 1-2x4' becomes '1 -1 -3 -5 -7' - series starts at 1, then 4 further samples decrementing by 2.
+#     3. ' 1x4' becomes '1 1 1 1 1' - shorthand for '1+0x4', series starts at 1, then 4 further samples incrementing by 0.
+#     4. ' 1 _x3 stale' becomes '1 _ _ _ stale' - the missing sample cannot increment, so 3 missing samples are produced by the '_x3' expression.
+values: <string>
+```
+
+#### `<alert_test_case>`
+
+vmalert by default adds `alertgroup` and `alertname` to the generated alerts and time series.
+So you will need to specify both `groupname` and `alertname` under a single `<alert_test_case>`,
+but no need to add them under `exp_alerts`.
+You can also pass `--disableAlertgroupLabel` to skip `alertgroup` check.
+
+```
+# The time elapsed from time=0s when this alerting rule should be checked.
+# Means this rule should be firing at this point, or shouldn't be firing if 'exp_alerts' is empty.
+eval_time: <duration>
+
+# Name of the group name to be tested.
+groupname: <string>
+
+# Name of the alert to be tested.
+alertname: <string>
+
+# List of the expected alerts that are firing under the given alertname at
+# the given evaluation time. If you want to test if an alerting rule should
+# not be firing, then you can mention only the fields above and leave 'exp_alerts' empty.
+exp_alerts:
+  [ - <alert> ]
+```
+
+#### `<alert>`
+
+```
+# These are the expanded labels and annotations of the expected alert.
+# Note: labels also include the labels of the sample associated with the alert
+exp_labels:
+  [ <labelname>: <string> ]
+exp_annotations:
+  [ <labelname>: <string> ]
+```
+
+#### `<metricsql_expr_test>`
+
+```
+# Expression to evaluate
+expr: <string>
+
+# The time elapsed from time=0s when this expression be evaluated.
+eval_time: <duration>
+
+# Expected samples at the given evaluation time.
+exp_samples:
+  [ - <sample> ]
+```
+
+#### `<sample>`
+
+```
+# Labels of the sample in usual series notation '<metric name>{<label name>=<label value>, ...}'
+# Examples:
+#      series_name{label1="value1", label2="value2"}
+#      go_goroutines{job="prometheus", instance="localhost:9090"}
+labels: <string>
+
+# The expected value of the Metricsql expression.
+value: <number>
+```
+
+### Example
+
+This is an example input file for unit testing which will pass.
+`test.yaml` is the test file which follows the syntax above and `alerts.yaml` contains the alerting rules.
+
+With `rules.yaml` in the same directory, run `./vmalert-tool unittest --files=./unittest/testdata/test.yaml`.
+
+#### `test.yaml`
+
+```
+rule_files:
+  - rules.yaml
+
+evaluation_interval: 1m
+
+tests:
+  - interval: 1m
+    input_series:
+      - series: 'up{job="prometheus", instance="localhost:9090"}'
+        values: "0+0x1440"
+
+    metricsql_expr_test:
+      - expr: suquery_interval_test
+        eval_time: 4m
+        exp_samples:
+          - labels: '{__name__="suquery_interval_test", datacenter="dc-123", instance="localhost:9090", job="prometheus"}'
+            value: 1
+
+    alert_rule_test:
+      - eval_time: 2h
+        groupname: group1
+        alertname: InstanceDown
+        exp_alerts:
+          - exp_labels:
+              job: prometheus
+              severity: page
+              instance: localhost:9090
+              datacenter: dc-123
+            exp_annotations:
+              summary: "Instance localhost:9090 down"
+              description: "localhost:9090 of job prometheus has been down for more than 5 minutes."
+
+      - eval_time: 0
+        groupname: group1
+        alertname: AlwaysFiring
+        exp_alerts:
+          - exp_labels:
+              datacenter: dc-123
+
+      - eval_time: 0
+        groupname: group1
+        alertname: InstanceDown
+        exp_alerts: []
+
+    external_labels:
+      datacenter: dc-123
+```
+
+#### `alerts.yaml`
+
+```
+# This is the rules file.
+
+groups:
+  - name: group1
+    rules:
+      - alert: InstanceDown
+        expr: up == 0
+        for: 5m
+        labels:
+          severity: page
+        annotations:
+          summary: "Instance {{ $labels.instance }} down"
+          description: "{{ $labels.instance }} of job {{ $labels.job }} has been down for more than 5 minutes."
+      - alert: AlwaysFiring
+        expr: 1
+
+  - name: group2
+    rules:
+      - record: job:test:count_over_time1m
+        expr: sum without(instance) (count_over_time(test[1m]))
+      - record: suquery_interval_test
+        expr: count_over_time(up[5m:])
+```
\ No newline at end of file
diff --git a/app/vmalert-tool/main.go b/app/vmalert-tool/main.go
new file mode 100644
index 000000000..790cebd8b
--- /dev/null
+++ b/app/vmalert-tool/main.go
@@ -0,0 +1,54 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"time"
+
+	"github.com/urfave/cli/v2"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert-tool/unittest"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/buildinfo"
+)
+
+func main() {
+	start := time.Now()
+	app := &cli.App{
+		Name:      "vmalert-tool",
+		Usage:     "VMAlert command-line tool",
+		UsageText: "More info in https://docs.victoriametrics.com/vmalert-tool.html",
+		Version:   buildinfo.Version,
+		Commands: []*cli.Command{
+			{
+				Name:      "unittest",
+				Usage:     "Run unittest for alerting and recording rules.",
+				UsageText: "More info in https://docs.victoriametrics.com/vmalert-tool.html#Unit-testing-for-rules",
+				Flags: []cli.Flag{
+					&cli.StringSliceFlag{
+						Name:     "files",
+						Usage:    "files to run unittest with. Supports an array of values separated by comma or specified via multiple flags.",
+						Required: true,
+					},
+					&cli.BoolFlag{
+						Name:     "disableAlertgroupLabel",
+						Usage:    "disable adding group's Name as label to generated alerts and time series.",
+						Required: false,
+					},
+				},
+				Action: func(c *cli.Context) error {
+					if failed := unittest.UnitTest(c.StringSlice("files"), c.Bool("disableAlertgroupLabel")); failed {
+						return fmt.Errorf("unittest failed")
+					}
+					return nil
+				},
+			},
+		},
+	}
+
+	err := app.Run(os.Args)
+	if err != nil {
+		log.Fatalln(err)
+	}
+	log.Printf("Total time: %v", time.Since(start))
+}
diff --git a/app/vmalert-tool/unittest/alerting.go b/app/vmalert-tool/unittest/alerting.go
new file mode 100644
index 000000000..a9ffe8a79
--- /dev/null
+++ b/app/vmalert-tool/unittest/alerting.go
@@ -0,0 +1,19 @@
+package unittest
+
+import (
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promutils"
+)
+
+// alertTestCase holds alert_rule_test cases defined in test file
+type alertTestCase struct {
+	EvalTime  *promutils.Duration `yaml:"eval_time"`
+	GroupName string              `yaml:"groupname"`
+	Alertname string              `yaml:"alertname"`
+	ExpAlerts []expAlert          `yaml:"exp_alerts"`
+}
+
+// expAlert holds exp_alerts defined in test file
+type expAlert struct {
+	ExpLabels      map[string]string `yaml:"exp_labels"`
+	ExpAnnotations map[string]string `yaml:"exp_annotations"`
+}
diff --git a/app/vmalert-tool/unittest/input.go b/app/vmalert-tool/unittest/input.go
new file mode 100644
index 000000000..af4254a80
--- /dev/null
+++ b/app/vmalert-tool/unittest/input.go
@@ -0,0 +1,182 @@
+package unittest
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/http"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+
+	testutil "github.com/VictoriaMetrics/VictoriaMetrics/app/victoria-metrics/test"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/decimal"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promutils"
+	"github.com/VictoriaMetrics/metricsql"
+)
+
+// series holds input_series defined in the test file
+type series struct {
+	Series string `yaml:"series"`
+	Values string `yaml:"values"`
+}
+
+// sequenceValue is an omittable value in a sequence of time series values.
+type sequenceValue struct {
+	Value   float64
+	Omitted bool
+}
+
+func httpWrite(address string, r io.Reader) {
+	resp, err := http.Post(address, "", r)
+	if err != nil {
+		logger.Fatalf("failed to send to storage: %v", err)
+	}
+	resp.Body.Close()
+}
+
+// writeInputSeries send input series to vmstorage and flush them
+func writeInputSeries(input []series, interval *promutils.Duration, startStamp time.Time, dst string) error {
+	r := testutil.WriteRequest{}
+	for _, data := range input {
+		expr, err := metricsql.Parse(data.Series)
+		if err != nil {
+			return fmt.Errorf("failed to parse series %s: %v", data.Series, err)
+		}
+		promvals, err := parseInputValue(data.Values, true)
+		if err != nil {
+			return fmt.Errorf("failed to parse input series value %s: %v", data.Values, err)
+		}
+		metricExpr, ok := expr.(*metricsql.MetricExpr)
+		if !ok {
+			return fmt.Errorf("failed to parse series %s to metric expr: %v", data.Series, err)
+		}
+		samples := make([]testutil.Sample, 0, len(promvals))
+		ts := startStamp
+		for _, v := range promvals {
+			if !v.Omitted {
+				samples = append(samples, testutil.Sample{
+					Timestamp: ts.UnixMilli(),
+					Value:     v.Value,
+				})
+			}
+			ts = ts.Add(interval.Duration())
+		}
+		var ls []testutil.Label
+		for _, filter := range metricExpr.LabelFilterss[0] {
+			ls = append(ls, testutil.Label{Name: filter.Label, Value: filter.Value})
+		}
+		r.Timeseries = append(r.Timeseries, testutil.TimeSeries{Labels: ls, Samples: samples})
+	}
+
+	data, err := testutil.Compress(r)
+	if err != nil {
+		return fmt.Errorf("failed to compress data: %v", err)
+	}
+	// write input series to vm
+	httpWrite(dst, bytes.NewBuffer(data))
+	vmstorage.Storage.DebugFlush()
+	return nil
+}
+
+// parseInputValue support input like "1", "1+1x1 _ -4 3+20x1", see more examples in test.
+func parseInputValue(input string, origin bool) ([]sequenceValue, error) {
+	var res []sequenceValue
+	items := strings.Split(input, " ")
+	reg := regexp.MustCompile(`\D?\d*\D?`)
+	for _, item := range items {
+		if item == "stale" {
+			res = append(res, sequenceValue{Value: decimal.StaleNaN})
+			continue
+		}
+		vals := reg.FindAllString(item, -1)
+		switch len(vals) {
+		case 1:
+			if vals[0] == "_" {
+				res = append(res, sequenceValue{Omitted: true})
+				continue
+			}
+			v, err := strconv.ParseFloat(vals[0], 64)
+			if err != nil {
+				return nil, err
+			}
+			res = append(res, sequenceValue{Value: v})
+			continue
+		case 2:
+			p1 := vals[0][:len(vals[0])-1]
+			v2, err := strconv.ParseInt(vals[1], 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			option := vals[0][len(vals[0])-1]
+			switch option {
+			case '+':
+				v1, err := strconv.ParseFloat(p1, 64)
+				if err != nil {
+					return nil, err
+				}
+				res = append(res, sequenceValue{Value: v1 + float64(v2)})
+			case 'x':
+				for i := int64(0); i <= v2; i++ {
+					if p1 == "_" {
+						if i == 0 {
+							i = 1
+						}
+						res = append(res, sequenceValue{Omitted: true})
+						continue
+					}
+					v1, err := strconv.ParseFloat(p1, 64)
+					if err != nil {
+						return nil, err
+					}
+					if !origin || v1 == 0 {
+						res = append(res, sequenceValue{Value: v1 * float64(i)})
+						continue
+					}
+					newVal := fmt.Sprintf("%s+0x%s", p1, vals[1])
+					newRes, err := parseInputValue(newVal, false)
+					if err != nil {
+						return nil, err
+					}
+					res = append(res, newRes...)
+					break
+				}
+
+			default:
+				return nil, fmt.Errorf("got invalid operation %b", option)
+			}
+		case 3:
+			r1, err := parseInputValue(fmt.Sprintf("%s%s", vals[1], vals[2]), false)
+			if err != nil {
+				return nil, err
+			}
+			p1 := vals[0][:len(vals[0])-1]
+			v1, err := strconv.ParseFloat(p1, 64)
+			if err != nil {
+				return nil, err
+			}
+			option := vals[0][len(vals[0])-1]
+			var isAdd bool
+			if option == '+' {
+				isAdd = true
+			}
+			for _, r := range r1 {
+				if isAdd {
+					res = append(res, sequenceValue{
+						Value: r.Value + v1,
+					})
+				} else {
+					res = append(res, sequenceValue{
+						Value: v1 - r.Value,
+					})
+				}
+			}
+		default:
+			return nil, fmt.Errorf("unsupported input %s", input)
+		}
+	}
+	return res, nil
+}
diff --git a/app/vmalert-tool/unittest/input_test.go b/app/vmalert-tool/unittest/input_test.go
new file mode 100644
index 000000000..5f74de98b
--- /dev/null
+++ b/app/vmalert-tool/unittest/input_test.go
@@ -0,0 +1,93 @@
+package unittest
+
+import (
+	"testing"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/decimal"
+)
+
+func TestParseInputValue(t *testing.T) {
+	testCases := []struct {
+		input  string
+		exp    []sequenceValue
+		failed bool
+	}{
+		{
+			"",
+			nil,
+			true,
+		},
+		{
+			"testfailed",
+			nil,
+			true,
+		},
+		// stale doesn't support operations
+		{
+			"stalex3",
+			nil,
+			true,
+		},
+		{
+			"-4",
+			[]sequenceValue{{Value: -4}},
+			false,
+		},
+		{
+			"_",
+			[]sequenceValue{{Omitted: true}},
+			false,
+		},
+		{
+			"stale",
+			[]sequenceValue{{Value: decimal.StaleNaN}},
+			false,
+		},
+		{
+			"-4x1",
+			[]sequenceValue{{Value: -4}, {Value: -4}},
+			false,
+		},
+		{
+			"_x1",
+			[]sequenceValue{{Omitted: true}},
+			false,
+		},
+		{
+			"1+1x4",
+			[]sequenceValue{{Value: 1}, {Value: 2}, {Value: 3}, {Value: 4}, {Value: 5}},
+			false,
+		},
+		{
+			"2-1x4",
+			[]sequenceValue{{Value: 2}, {Value: 1}, {Value: 0}, {Value: -1}, {Value: -2}},
+			false,
+		},
+		{
+			"1+1x1 _ -4 stale 3+20x1",
+			[]sequenceValue{{Value: 1}, {Value: 2}, {Omitted: true}, {Value: -4}, {Value: decimal.StaleNaN}, {Value: 3}, {Value: 23}},
+			false,
+		},
+	}
+
+	for _, tc := range testCases {
+		output, err := parseInputValue(tc.input, true)
+		if err != nil != tc.failed {
+			t.Fatalf("failed to parse %s, expect %t, got %t", tc.input, tc.failed, err != nil)
+		}
+		if len(tc.exp) != len(output) {
+			t.Fatalf("expect %v, got %v", tc.exp, output)
+		}
+		for i := 0; i < len(tc.exp); i++ {
+			if tc.exp[i].Omitted != output[i].Omitted {
+				t.Fatalf("expect %v, got %v", tc.exp, output)
+			}
+			if tc.exp[i].Value != output[i].Value {
+				if decimal.IsStaleNaN(tc.exp[i].Value) && decimal.IsStaleNaN(output[i].Value) {
+					continue
+				}
+				t.Fatalf("expect %v, got %v", tc.exp, output)
+			}
+		}
+	}
+}
diff --git a/app/vmalert-tool/unittest/recording.go b/app/vmalert-tool/unittest/recording.go
new file mode 100644
index 000000000..5f275ead4
--- /dev/null
+++ b/app/vmalert-tool/unittest/recording.go
@@ -0,0 +1,92 @@
+package unittest
+
+import (
+	"context"
+	"fmt"
+	"net/url"
+	"reflect"
+	"sort"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promutils"
+	"github.com/VictoriaMetrics/metricsql"
+)
+
+// metricsqlTestCase holds metricsql_expr_test cases defined in test file
+type metricsqlTestCase struct {
+	Expr       string              `yaml:"expr"`
+	EvalTime   *promutils.Duration `yaml:"eval_time"`
+	ExpSamples []expSample         `yaml:"exp_samples"`
+}
+
+type expSample struct {
+	Labels string  `yaml:"labels"`
+	Value  float64 `yaml:"value"`
+}
+
+// checkMetricsqlCase will check metricsql_expr_test cases
+func checkMetricsqlCase(cases []metricsqlTestCase, q datasource.QuerierBuilder) (checkErrs []error) {
+	queries := q.BuildWithParams(datasource.QuerierParams{QueryParams: url.Values{"nocache": {"1"}, "latency_offset": {"1ms"}}, DataSourceType: "prometheus"})
+Outer:
+	for _, mt := range cases {
+		result, _, err := queries.Query(context.Background(), mt.Expr, mt.EvalTime.ParseTime())
+		if err != nil {
+			checkErrs = append(checkErrs, fmt.Errorf("    expr: %q, time: %s, err: %w", mt.Expr,
+				mt.EvalTime.Duration().String(), err))
+			continue
+		}
+		var gotSamples []parsedSample
+		for _, s := range result.Data {
+			sort.Slice(s.Labels, func(i, j int) bool {
+				return s.Labels[i].Name < s.Labels[j].Name
+			})
+			gotSamples = append(gotSamples, parsedSample{
+				Labels: s.Labels,
+				Value:  s.Values[0],
+			})
+		}
+		var expSamples []parsedSample
+		for _, s := range mt.ExpSamples {
+			expLb := datasource.Labels{}
+			if s.Labels != "" {
+				metricsqlExpr, err := metricsql.Parse(s.Labels)
+				if err != nil {
+					checkErrs = append(checkErrs, fmt.Errorf("\n    expr: %q, time: %s, err: %v", mt.Expr,
+						mt.EvalTime.Duration().String(), fmt.Errorf("failed to parse labels %q: %w", s.Labels, err)))
+					continue Outer
+				}
+				metricsqlMetricExpr, ok := metricsqlExpr.(*metricsql.MetricExpr)
+				if !ok {
+					checkErrs = append(checkErrs, fmt.Errorf("\n    expr: %q, time: %s, err: %v", mt.Expr,
+						mt.EvalTime.Duration().String(), fmt.Errorf("got unsupported metricsql type")))
+					continue Outer
+				}
+				for _, l := range metricsqlMetricExpr.LabelFilterss[0] {
+					expLb = append(expLb, datasource.Label{
+						Name:  l.Label,
+						Value: l.Value,
+					})
+				}
+			}
+			sort.Slice(expLb, func(i, j int) bool {
+				return expLb[i].Name < expLb[j].Name
+			})
+			expSamples = append(expSamples, parsedSample{
+				Labels: expLb,
+				Value:  s.Value,
+			})
+		}
+		sort.Slice(expSamples, func(i, j int) bool {
+			return datasource.LabelCompare(expSamples[i].Labels, expSamples[j].Labels) <= 0
+		})
+		sort.Slice(gotSamples, func(i, j int) bool {
+			return datasource.LabelCompare(gotSamples[i].Labels, gotSamples[j].Labels) <= 0
+		})
+		if !reflect.DeepEqual(expSamples, gotSamples) {
+			checkErrs = append(checkErrs, fmt.Errorf("\n    expr: %q, time: %s,\n        exp: %v\n        got: %v", mt.Expr,
+				mt.EvalTime.Duration().String(), parsedSamplesString(expSamples), parsedSamplesString(gotSamples)))
+		}
+
+	}
+	return
+}
diff --git a/app/vmalert-tool/unittest/testdata/disable-group-label.yaml b/app/vmalert-tool/unittest/testdata/disable-group-label.yaml
new file mode 100644
index 000000000..6060710b6
--- /dev/null
+++ b/app/vmalert-tool/unittest/testdata/disable-group-label.yaml
@@ -0,0 +1,43 @@
+rule_files:
+  - rules.yaml
+
+evaluation_interval: 1m
+
+tests:
+  - interval: 1m
+    input_series:
+      - series: 'up{job="vmagent2", instance="localhost:9090"}'
+        values: "0+0x1440"
+
+    metricsql_expr_test:
+      - expr: suquery_interval_test
+        eval_time: 4m
+        exp_samples:
+          - labels: '{__name__="suquery_interval_test",datacenter="dc-123", instance="localhost:9090", job="vmagent2"}'
+            value: 1
+
+    alert_rule_test:
+      - eval_time: 2h
+        alertname: InstanceDown
+        exp_alerts:
+          - exp_labels:
+              job: vmagent2
+              severity: page
+              instance: localhost:9090
+              datacenter: dc-123
+            exp_annotations:
+              summary: "Instance localhost:9090 down"
+              description: "localhost:9090 of job vmagent2 has been down for more than 5 minutes."
+
+      - eval_time: 0
+        alertname: AlwaysFiring
+        exp_alerts:
+          - exp_labels:
+              datacenter: dc-123
+
+      - eval_time: 0
+        alertname: InstanceDown
+        exp_alerts: []
+
+    external_labels:
+      datacenter: dc-123
diff --git a/app/vmalert-tool/unittest/testdata/failed-test.yaml b/app/vmalert-tool/unittest/testdata/failed-test.yaml
new file mode 100644
index 000000000..0a1de6365
--- /dev/null
+++ b/app/vmalert-tool/unittest/testdata/failed-test.yaml
@@ -0,0 +1,49 @@
+rule_files:
+  - rules.yaml
+
+tests:
+  - interval: 1m
+    name: "Failing test"
+    input_series:
+      - series: test
+        values: "0"
+
+    metricsql_expr_test:
+      - expr: test
+        eval_time: 0m
+        exp_samples:
+          - value: 0
+            labels: test
+
+    # will failed cause there is no "Test" group and rule defined
+    alert_rule_test:
+      - eval_time: 0m
+        groupname: Test
+        alertname: Test
+        exp_alerts:
+          - exp_labels: {}
+
+  - interval: 1m
+    name: Failing alert test
+    input_series:
+      - series: 'up{job="test"}'
+        values: 0x10
+
+    alert_rule_test:
+      # will failed cause rule is firing
+      - eval_time: 5m
+        groupname: group1
+        alertname: InstanceDown
+        exp_alerts: []
+
+  - interval: 1m
+    name: Failing alert test with missing groupname
+    input_series:
+      - series: 'up{job="test"}'
+        values: 0x10
+
+    alert_rule_test:
+      # will failed cause missing groupname
+      - eval_time: 5m
+        alertname: AlwaysFiring
+        exp_alerts: []
diff --git a/app/vmalert-tool/unittest/testdata/long-period.yaml b/app/vmalert-tool/unittest/testdata/long-period.yaml
new file mode 100644
index 000000000..052470b69
--- /dev/null
+++ b/app/vmalert-tool/unittest/testdata/long-period.yaml
@@ -0,0 +1,30 @@
+# can be executed successfully but will take more than 1 minute
+# not included in unit test now
+evaluation_interval: 100d
+
+rule_files:
+  - rules.yaml
+
+tests:
+  - interval: 1d
+    input_series:
+      - series: test
+        # Max time in time.Duration is 106751d from 1970 (2^63/10^9), i.e. 2262.
+        # But VictoriaMetrics supports maxTimestamp value +2 days from now. see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/827.
+        # We input series to 2024-01-01T00:00:00 here.
+        values: "0+1x19723"
+
+    metricsql_expr_test:
+      - expr: timestamp(test)
+        eval_time: 0m
+        exp_samples:
+          - value: 0
+      - expr: test
+        eval_time: 100d
+        exp_samples:
+          - labels: test
+            value: 100
+      - expr: timestamp(test)
+        eval_time: 19000d
+        exp_samples:
+          - value: 1641600000 # 19000d -> seconds.
diff --git a/app/vmalert-tool/unittest/testdata/rules.yaml b/app/vmalert-tool/unittest/testdata/rules.yaml
new file mode 100644
index 000000000..f7455c6d8
--- /dev/null
+++ b/app/vmalert-tool/unittest/testdata/rules.yaml
@@ -0,0 +1,39 @@
+groups:
+  - name: group1
+    rules:
+      - alert: InstanceDown
+        expr: up == 0
+        for: 5m
+        labels:
+          severity: page
+        annotations:
+          summary: "Instance {{ $labels.instance }} down"
+          description: "{{ $labels.instance }} of job {{ $labels.job }} has been down for more than 5 minutes."
+      - alert: AlwaysFiring
+        expr: 1
+      - alert: SameAlertNameWithDifferentGroup
+        expr: absent(test)
+        for: 1m
+
+  - name: group2
+    rules:
+      - record: t1
+        expr: test
+      - record: job:test:count_over_time1m
+        expr: sum without(instance) (count_over_time(test[1m]))
+      - record: suquery_interval_test
+        expr: count_over_time(up[5m:])
+
+      - alert: SameAlertNameWithDifferentGroup
+        expr: absent(test)
+        for: 5m
+
+  - name: group3
+    rules:
+      - record: t2
+        expr: t1
+
+  - name: group4
+    rules:
+      - record: t3
+        expr: t1
diff --git a/app/vmalert-tool/unittest/testdata/test1.yaml b/app/vmalert-tool/unittest/testdata/test1.yaml
new file mode 100644
index 000000000..d60e8587f
--- /dev/null
+++ b/app/vmalert-tool/unittest/testdata/test1.yaml
@@ -0,0 +1,99 @@
+rule_files:
+  - rules.yaml
+
+evaluation_interval: 1m
+group_eval_order: ["group4", "group2", "group3"]
+
+tests:
+  - interval: 1m
+    name: "basic test"
+    input_series:
+      - series: "test"
+        values: "_x5 1x5 _ stale"
+
+    alert_rule_test:
+      - eval_time: 1m
+        groupname: group1
+        alertname: SameAlertNameWithDifferentGroup
+        exp_alerts:
+          - {}
+      - eval_time: 1m
+        groupname: group2
+        alertname: SameAlertNameWithDifferentGroup
+        exp_alerts: []
+      - eval_time: 6m
+        groupname: group1
+        alertname: SameAlertNameWithDifferentGroup
+        exp_alerts: []
+
+    metricsql_expr_test:
+      - expr: test
+        eval_time: 11m
+        exp_samples:
+          - labels: '{__name__="test"}'
+            value: 1
+      - expr: test
+        eval_time: 12m
+        exp_samples: []
+
+  - interval: 1m
+    name: "basic test2"
+    input_series:
+      - series: 'up{job="vmagent1", instance="localhost:9090"}'
+        values: "0+0x1440"
+      - series: "test"
+        values: "0+1x1440"
+
+    metricsql_expr_test:
+      - expr: count(ALERTS) by (alertgroup, alertname, alertstate)
+        eval_time: 4m
+        exp_samples:
+          - labels: '{alertgroup="group1", alertname="AlwaysFiring", alertstate="firing"}'
+            value: 1
+          - labels: '{alertgroup="group1", alertname="InstanceDown", alertstate="pending"}'
+            value: 1
+      - expr: t1
+        eval_time: 4m
+        exp_samples:
+          - value: 4
+            labels: '{__name__="t1", datacenter="dc-123"}'
+      - expr: t2
+        eval_time: 4m
+        exp_samples:
+          - value: 4
+            labels: '{__name__="t2", datacenter="dc-123"}'
+      - expr: t3
+        eval_time: 4m
+        exp_samples:
+          # t3 is 3 instead of 4 cause it's rules3 is evaluated before rules1
+          - value: 3
+            labels: '{__name__="t3", datacenter="dc-123"}'
+
+    alert_rule_test:
+      - eval_time: 10m
+        groupname: group1
+        alertname: InstanceDown
+        exp_alerts:
+          - exp_labels:
+              job: vmagent1
+              severity: page
+              instance: localhost:9090
+              datacenter: dc-123
+            exp_annotations:
+              summary: "Instance localhost:9090 down"
+              description: "localhost:9090 of job vmagent1 has been down for more than 5 minutes."
+
+      - eval_time: 0
+        groupname: group1
+        alertname: AlwaysFiring
+        exp_alerts:
+          - exp_labels:
+              datacenter: dc-123
+
+      - eval_time: 0
+        groupname: alerts
+        alertname: InstanceDown
+        exp_alerts: []
+
+    external_labels:
+      datacenter: dc-123
diff --git a/app/vmalert-tool/unittest/testdata/test2.yaml b/app/vmalert-tool/unittest/testdata/test2.yaml
new file mode 100644
index 000000000..2d7825742
--- /dev/null
+++ b/app/vmalert-tool/unittest/testdata/test2.yaml
@@ -0,0 +1,46 @@
+rule_files:
+  - rules.yaml
+
+evaluation_interval: 1m
+
+tests:
+  - interval: 1m
+    input_series:
+      - series: 'up{job="vmagent2", instance="localhost:9090"}'
+        values: "0+0x1440"
+
+    metricsql_expr_test:
+      - expr: suquery_interval_test
+        eval_time: 4m
+        exp_samples:
+          - labels: '{__name__="suquery_interval_test",datacenter="dc-123", instance="localhost:9090", job="vmagent2"}'
+            value: 1
+
+    alert_rule_test:
+      - eval_time: 2h
+        groupname: group1
+        alertname: InstanceDown
+        exp_alerts:
+          - exp_labels:
+              job: vmagent2
+              severity: page
+              instance: localhost:9090
+              datacenter: dc-123
+            exp_annotations:
+              summary: "Instance localhost:9090 down"
+              description: "localhost:9090 of job vmagent2 has been down for more than 5 minutes."
+
+      - eval_time: 0
+        groupname: group1
+        alertname: AlwaysFiring
+        exp_alerts:
+          - exp_labels:
+              datacenter: dc-123
+
+      - eval_time: 0
+        groupname: group1
+        alertname: InstanceDown
+        exp_alerts: []
+
+    external_labels:
+      datacenter: dc-123
diff --git a/app/vmalert-tool/unittest/type.go b/app/vmalert-tool/unittest/type.go
new file mode 100644
index 000000000..8915a8f5c
--- /dev/null
+++ b/app/vmalert-tool/unittest/type.go
@@ -0,0 +1,83 @@
+package unittest
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
+)
+
+// parsedSample is a sample with parsed Labels
+type parsedSample struct {
+	Labels datasource.Labels
+	Value  float64
+}
+
+func (ps *parsedSample) String() string {
+	return ps.Labels.String() + " " + strconv.FormatFloat(ps.Value, 'E', -1, 64)
+}
+
+func parsedSamplesString(pss []parsedSample) string {
+	if len(pss) == 0 {
+		return "nil"
+	}
+	s := pss[0].String()
+	for _, ps := range pss[1:] {
+		s += ", " + ps.String()
+	}
+	return s
+}
+
+// labelAndAnnotation holds labels and annotations
+type labelAndAnnotation struct {
+	Labels      datasource.Labels
+	Annotations datasource.Labels
+}
+
+func (la *labelAndAnnotation) String() string {
+	return "Labels:" + la.Labels.String() + "\nAnnotations:" + la.Annotations.String()
+}
+
+// labelsAndAnnotations is collection of LabelAndAnnotation
+type labelsAndAnnotations []labelAndAnnotation
+
+func (la labelsAndAnnotations) Len() int { return len(la) }
+
+func (la labelsAndAnnotations) Swap(i, j int) { la[i], la[j] = la[j], la[i] }
+func (la labelsAndAnnotations) Less(i, j int) bool {
+	diff := datasource.LabelCompare(la[i].Labels, la[j].Labels)
+	if diff != 0 {
+		return diff < 0
+	}
+	return datasource.LabelCompare(la[i].Annotations, la[j].Annotations) < 0
+}
+
+func (la labelsAndAnnotations) String() string {
+	if len(la) == 0 {
+		return "[]"
+	}
+	s := "[\n0:" + indentLines("\n"+la[0].String(), "  ")
+	for i, l := range la[1:] {
+		s += ",\n" + fmt.Sprintf("%d", i+1) + ":" + indentLines("\n"+l.String(), "  ")
+	}
+	s += "\n]"
+
+	return s
+}
+
+// indentLines prefixes each line in the supplied string with the given "indent" string.
+func indentLines(lines, indent string) string {
+	sb := strings.Builder{}
+	n := strings.Split(lines, "\n")
+	for i, l := range n {
+		if i > 0 {
+			sb.WriteString(indent)
+		}
+		sb.WriteString(l)
+		if i != len(n)-1 {
+			sb.WriteRune('\n')
+		}
+	}
+	return sb.String()
+}
diff --git a/app/vmalert-tool/unittest/unittest.go b/app/vmalert-tool/unittest/unittest.go
new file mode 100644
index 000000000..424a6132e
--- /dev/null
+++ b/app/vmalert-tool/unittest/unittest.go
@@ -0,0 +1,443 @@
+package unittest
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"net/http"
+	"os"
+	"path/filepath"
+	"reflect"
+	"sort"
+	"time"
+
+	"gopkg.in/yaml.v2"
+
+	vmalertconfig "github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/templates"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vminsert"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vminsert/promremotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect/prometheus"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect/promql"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/fs"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promutils"
+	"github.com/VictoriaMetrics/metrics"
+)
+
+var (
+	storagePath    string
+	httpListenAddr = ":8880"
+	// insert series from 1970-01-01T00:00:00
+	testStartTime = time.Unix(0, 0).UTC()
+
+	testPromWriteHTTPPath = "http://127.0.0.1" + httpListenAddr + "/api/v1/write"
+	testDataSourcePath    = "http://127.0.0.1" + httpListenAddr + "/prometheus"
+	testRemoteWritePath   = "http://127.0.0.1" + httpListenAddr
+	testHealthHTTPPath    = "http://127.0.0.1" + httpListenAddr + "/health"
+
+	disableAlertgroupLabel bool
+)
+
+const (
+	testStoragePath = "vmalert-unittest"
+	testLogLevel    = "ERROR"
+)
+
+// UnitTest runs unittest for files
+func UnitTest(files []string, disableGroupLabel bool) bool {
+	if err := templates.Load([]string{}, true); err != nil {
+		logger.Fatalf("failed to load template: %v", err)
+	}
+	storagePath = filepath.Join(os.TempDir(), testStoragePath)
+	processFlags()
+	vminsert.Init()
+	vmselect.Init()
+	// storagePath will be created again when closing vmselect, so remove it again.
+	defer fs.MustRemoveAll(storagePath)
+	defer vminsert.Stop()
+	defer vmselect.Stop()
+	disableAlertgroupLabel = disableGroupLabel
+	return rulesUnitTest(files)
+}
+
+func rulesUnitTest(files []string) bool {
+	var failed bool
+	for _, f := range files {
+		if err := ruleUnitTest(f); err != nil {
+			fmt.Println("  FAILED")
+			fmt.Printf("\nfailed to run unit test for file %q: \n%v", f, err)
+			failed = true
+		} else {
+			fmt.Println("  SUCCESS")
+		}
+	}
+	return failed
+}
+
+func ruleUnitTest(filename string) []error {
+	fmt.Println("\nUnit Testing: ", filename)
+	b, err := os.ReadFile(filename)
+	if err != nil {
+		return []error{fmt.Errorf("failed to read file: %w", err)}
+	}
+
+	var unitTestInp unitTestFile
+	if err := yaml.UnmarshalStrict(b, &unitTestInp); err != nil {
+		return []error{fmt.Errorf("failed to unmarshal file: %w", err)}
+	}
+	if err := resolveAndGlobFilepaths(filepath.Dir(filename), &unitTestInp); err != nil {
+		return []error{fmt.Errorf("failed to resolve path for `rule_files`: %w", err)}
+	}
+
+	if unitTestInp.EvaluationInterval.Duration() == 0 {
+		fmt.Println("evaluation_interval set to 1m by default")
+		unitTestInp.EvaluationInterval = &promutils.Duration{D: 1 * time.Minute}
+	}
+
+	groupOrderMap := make(map[string]int)
+	for i, gn := range unitTestInp.GroupEvalOrder {
+		if _, ok := groupOrderMap[gn]; ok {
+			return []error{fmt.Errorf("group name repeated in `group_eval_order`: %s", gn)}
+		}
+		groupOrderMap[gn] = i
+	}
+
+	testGroups, err := vmalertconfig.Parse(unitTestInp.RuleFiles, nil, true)
+	if err != nil {
+		return []error{fmt.Errorf("failed to parse `rule_files`: %w", err)}
+	}
+
+	var errs []error
+	for _, t := range unitTestInp.Tests {
+		if err := verifyTestGroup(t); err != nil {
+			errs = append(errs, err)
+			continue
+		}
+		testErrs := t.test(unitTestInp.EvaluationInterval.Duration(), groupOrderMap, testGroups)
+		errs = append(errs, testErrs...)
+	}
+
+	if len(errs) > 0 {
+		return errs
+	}
+	return nil
+}
+
+func verifyTestGroup(group testGroup) error {
+	var testGroupName string
+	if group.TestGroupName != "" {
+		testGroupName = fmt.Sprintf("testGroupName: %s\n", group.TestGroupName)
+	}
+	for _, at := range group.AlertRuleTests {
+		if at.Alertname == "" {
+			return fmt.Errorf("\n%s    missing required filed \"alertname\"", testGroupName)
+		}
+		if !disableAlertgroupLabel && at.GroupName == "" {
+			return fmt.Errorf("\n%s    missing required filed \"groupname\" when flag \"disableAlertGroupLabel\" is false", testGroupName)
+		}
+		if disableAlertgroupLabel && at.GroupName != "" {
+			return fmt.Errorf("\n%s    shouldn't set filed \"groupname\" when flag \"disableAlertGroupLabel\" is true", testGroupName)
+		}
+		if at.EvalTime == nil {
+			return fmt.Errorf("\n%s    missing required filed \"eval_time\"", testGroupName)
+		}
+	}
+	for _, et := range group.MetricsqlExprTests {
+		if et.Expr == "" {
+			return fmt.Errorf("\n%s    missing required filed \"expr\"", testGroupName)
+		}
+		if et.EvalTime == nil {
+			return fmt.Errorf("\n%s    missing required filed \"eval_time\"", testGroupName)
+		}
+	}
+	return nil
+}
+
+func processFlags() {
+	flag.Parse()
+	for _, fv := range []struct {
+		flag  string
+		value string
+	}{
+		{flag: "storageDataPath", value: storagePath},
+		{flag: "loggerLevel", value: testLogLevel},
+		{flag: "search.disableCache", value: "true"},
+		// set storage retention time to 100 years, allow to store series from 1970-01-01T00:00:00.
+		{flag: "retentionPeriod", value: "100y"},
+		{flag: "datasource.url", value: testDataSourcePath},
+		{flag: "remoteWrite.url", value: testRemoteWritePath},
+	} {
+		// panics if flag doesn't exist
+		if err := flag.Lookup(fv.flag).Value.Set(fv.value); err != nil {
+			logger.Fatalf("unable to set %q with value %q, err: %v", fv.flag, fv.value, err)
+		}
+	}
+}
+
+func setUp() {
+	vmstorage.Init(promql.ResetRollupResultCacheIfNeeded)
+	go httpserver.Serve(httpListenAddr, false, func(w http.ResponseWriter, r *http.Request) bool {
+		switch r.URL.Path {
+		case "/prometheus/api/v1/query":
+			if err := prometheus.QueryHandler(nil, time.Now(), w, r); err != nil {
+				httpserver.Errorf(w, r, "%s", err)
+			}
+			return true
+		case "/prometheus/api/v1/write", "/api/v1/write":
+			if err := promremotewrite.InsertHandler(r); err != nil {
+				httpserver.Errorf(w, r, "%s", err)
+			}
+			return true
+		default:
+		}
+		return false
+	})
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+	readyCheckFunc := func() bool {
+		resp, err := http.Get(testHealthHTTPPath)
+		if err != nil {
+			return false
+		}
+		_ = resp.Body.Close()
+		return resp.StatusCode == 200
+	}
+checkCheck:
+	for {
+		select {
+		case <-ctx.Done():
+			logger.Fatalf("http server can't be ready in 30s")
+		default:
+			if readyCheckFunc() {
+				break checkCheck
+			}
+			time.Sleep(3 * time.Second)
+		}
+	}
+}
+
+func tearDown() {
+	if err := httpserver.Stop(httpListenAddr); err != nil {
+		logger.Errorf("cannot stop the webservice: %s", err)
+	}
+	vmstorage.Stop()
+	metrics.UnregisterAllMetrics()
+	fs.MustRemoveAll(storagePath)
+}
+
+// resolveAndGlobFilepaths joins all relative paths in a configuration
+// with a given base directory and replaces all globs with matching files.
+func resolveAndGlobFilepaths(baseDir string, utf *unitTestFile) error {
+	for i, rf := range utf.RuleFiles {
+		if rf != "" && !filepath.IsAbs(rf) {
+			utf.RuleFiles[i] = filepath.Join(baseDir, rf)
+		}
+	}
+
+	var globbedFiles []string
+	for _, rf := range utf.RuleFiles {
+		m, err := filepath.Glob(rf)
+		if err != nil {
+			return err
+		}
+		if len(m) == 0 {
+			fmt.Fprintln(os.Stderr, "  WARNING: no file match pattern", rf)
+		}
+		globbedFiles = append(globbedFiles, m...)
+	}
+	utf.RuleFiles = globbedFiles
+	return nil
+}
+
+func (tg *testGroup) test(evalInterval time.Duration, groupOrderMap map[string]int, testGroups []vmalertconfig.Group) (checkErrs []error) {
+	// set up vmstorage and http server for ingest and read queries
+	setUp()
+	// tear down vmstorage and clean the data dir
+	defer tearDown()
+
+	err := writeInputSeries(tg.InputSeries, tg.Interval, testStartTime, testPromWriteHTTPPath)
+	if err != nil {
+		return []error{err}
+	}
+
+	q, err := datasource.Init(nil)
+	if err != nil {
+		return []error{fmt.Errorf("failed to init datasource: %v", err)}
+	}
+	rw, err := remotewrite.NewDebugClient()
+	if err != nil {
+		return []error{fmt.Errorf("failed to init wr: %v", err)}
+	}
+
+	alertEvalTimesMap := map[time.Duration]struct{}{}
+	alertExpResultMap := map[time.Duration]map[string]map[string][]expAlert{}
+	for _, at := range tg.AlertRuleTests {
+		et := at.EvalTime.Duration()
+		alertEvalTimesMap[et] = struct{}{}
+		if _, ok := alertExpResultMap[et]; !ok {
+			alertExpResultMap[et] = make(map[string]map[string][]expAlert)
+		}
+		if _, ok := alertExpResultMap[et][at.GroupName]; !ok {
+			alertExpResultMap[et][at.GroupName] = make(map[string][]expAlert)
+		}
+		alertExpResultMap[et][at.GroupName][at.Alertname] = at.ExpAlerts
+	}
+	alertEvalTimes := make([]time.Duration, 0, len(alertEvalTimesMap))
+	for k := range alertEvalTimesMap {
+		alertEvalTimes = append(alertEvalTimes, k)
+	}
+	sort.Slice(alertEvalTimes, func(i, j int) bool {
+		return alertEvalTimes[i] < alertEvalTimes[j]
+	})
+
+	// sort group eval order according to the given "group_eval_order".
+	sort.Slice(testGroups, func(i, j int) bool {
+		return groupOrderMap[testGroups[i].Name] < groupOrderMap[testGroups[j].Name]
+	})
+
+	// create groups with given rule
+	var groups []*rule.Group
+	for _, group := range testGroups {
+		ng := rule.NewGroup(group, q, time.Minute, tg.ExternalLabels)
+		groups = append(groups, ng)
+	}
+
+	evalIndex := 0
+	maxEvalTime := testStartTime.Add(tg.maxEvalTime())
+	for ts := testStartTime; ts.Before(maxEvalTime) || ts.Equal(maxEvalTime); ts = ts.Add(evalInterval) {
+		for _, g := range groups {
+			errs := g.ExecOnce(context.Background(), func() []notifier.Notifier { return nil }, rw, ts)
+			for err := range errs {
+				if err != nil {
+					checkErrs = append(checkErrs, fmt.Errorf("\nfailed to exec group: %q, time: %s, err: %w", g.Name,
+						ts, err))
+				}
+			}
+			// flush series after each group evaluation
+			vmstorage.Storage.DebugFlush()
+		}
+
+		// check alert_rule_test case at every eval time
+		for evalIndex < len(alertEvalTimes) {
+			if ts.Sub(testStartTime) > alertEvalTimes[evalIndex] ||
+				alertEvalTimes[evalIndex] >= ts.Add(evalInterval).Sub(testStartTime) {
+				break
+			}
+			gotAlertsMap := map[string]map[string]labelsAndAnnotations{}
+			for _, g := range groups {
+				if disableAlertgroupLabel {
+					g.Name = ""
+				}
+				if _, ok := alertExpResultMap[time.Duration(ts.UnixNano())][g.Name]; !ok {
+					continue
+				}
+				if _, ok := gotAlertsMap[g.Name]; !ok {
+					gotAlertsMap[g.Name] = make(map[string]labelsAndAnnotations)
+				}
+				for _, r := range g.Rules {
+					ar, isAlertRule := r.(*rule.AlertingRule)
+					if !isAlertRule {
+						continue
+					}
+					if _, ok := alertExpResultMap[time.Duration(ts.UnixNano())][g.Name][ar.Name]; ok {
+						for _, got := range ar.GetAlerts() {
+							if got.State != notifier.StateFiring {
+								continue
+							}
+							if disableAlertgroupLabel {
+								delete(got.Labels, "alertgroup")
+							}
+							laa := labelAndAnnotation{
+								Labels:      datasource.ConvertToLabels(got.Labels),
+								Annotations: datasource.ConvertToLabels(got.Annotations),
+							}
+							gotAlertsMap[g.Name][ar.Name] = append(gotAlertsMap[g.Name][ar.Name], laa)
+						}
+					}
+
+				}
+			}
+			for groupname, gres := range alertExpResultMap[alertEvalTimes[evalIndex]] {
+				for alertname, res := range gres {
+					var expAlerts labelsAndAnnotations
+					for _, expAlert := range res {
+						if expAlert.ExpLabels == nil {
+							expAlert.ExpLabels = make(map[string]string)
+						}
+						// alertGroupNameLabel is added as additional labels when `disableAlertGroupLabel` is false
+						if !disableAlertgroupLabel {
+							expAlert.ExpLabels["alertgroup"] = groupname
+						}
+						// alertNameLabel is added as additional labels in vmalert.
+						expAlert.ExpLabels["alertname"] = alertname
+						expAlerts = append(expAlerts, labelAndAnnotation{
+							Labels:      datasource.ConvertToLabels(expAlert.ExpLabels),
+							Annotations: datasource.ConvertToLabels(expAlert.ExpAnnotations),
+						})
+					}
+					sort.Sort(expAlerts)
+
+					gotAlerts := gotAlertsMap[groupname][alertname]
+					sort.Sort(gotAlerts)
+					if !reflect.DeepEqual(expAlerts, gotAlerts) {
+						var testGroupName string
+						if tg.TestGroupName != "" {
+							testGroupName = fmt.Sprintf("testGroupName: %s,\n", tg.TestGroupName)
+						}
+						expString := indentLines(expAlerts.String(), "            ")
+						gotString := indentLines(gotAlerts.String(), "            ")
+						checkErrs = append(checkErrs, fmt.Errorf("\n%s    groupname: %s, alertname: %s, time: %s, \n        exp:%v, \n        got:%v ",
+							testGroupName, groupname, alertname, alertEvalTimes[evalIndex].String(), expString, gotString))
+					}
+				}
+			}
+			evalIndex++
+		}
+
+	}
+
+	checkErrs = append(checkErrs, checkMetricsqlCase(tg.MetricsqlExprTests, q)...)
+	return checkErrs
+}
+
+// unitTestFile holds the contents of a single unit test file
+type unitTestFile struct {
+	RuleFiles          []string            `yaml:"rule_files"`
+	EvaluationInterval *promutils.Duration `yaml:"evaluation_interval"`
+	GroupEvalOrder     []string            `yaml:"group_eval_order"`
+	Tests              []testGroup         `yaml:"tests"`
+}
+
+// testGroup is a group of input series and test cases associated with it
+type testGroup struct {
+	Interval           *promutils.Duration `yaml:"interval"`
+	InputSeries        []series            `yaml:"input_series"`
+	AlertRuleTests     []alertTestCase     `yaml:"alert_rule_test"`
+	MetricsqlExprTests []metricsqlTestCase `yaml:"metricsql_expr_test"`
+	ExternalLabels     map[string]string   `yaml:"external_labels"`
+	TestGroupName      string              `yaml:"name"`
+}
+
+// maxEvalTime returns the max eval time among all alert_rule_test and metricsql_expr_test
+func (tg *testGroup) maxEvalTime() time.Duration {
+	var maxd time.Duration
+	for _, alert := range tg.AlertRuleTests {
+		if alert.EvalTime.Duration() > maxd {
+			maxd = alert.EvalTime.Duration()
+		}
+	}
+	for _, met := range tg.MetricsqlExprTests {
+		if met.EvalTime.Duration() > maxd {
+			maxd = met.EvalTime.Duration()
+		}
+	}
+	return maxd
+}
diff --git a/app/vmalert-tool/unittest/unittest_test.go b/app/vmalert-tool/unittest/unittest_test.go
new file mode 100644
index 000000000..c2c014d6e
--- /dev/null
+++ b/app/vmalert-tool/unittest/unittest_test.go
@@ -0,0 +1,47 @@
+package unittest
+
+import (
+	"os"
+	"testing"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/templates"
+)
+
+func TestMain(m *testing.M) {
+	if err := templates.Load([]string{}, true); err != nil {
+		os.Exit(1)
+	}
+	os.Exit(m.Run())
+}
+
+func TestUnitRule(t *testing.T) {
+	testCases := []struct {
+		name              string
+		disableGroupLabel bool
+		files             []string
+		failed            bool
+	}{
+		{
+			name:   "run multi files",
+			files:  []string{"./testdata/test1.yaml", "./testdata/test2.yaml"},
+			failed: false,
+		},
+		{
+			name:              "disable group label",
+			disableGroupLabel: true,
+			files:             []string{"./testdata/disable-group-label.yaml"},
+			failed:            false,
+		},
+		{
+			name:   "failing test",
+			files:  []string{"./testdata/failed-test.yaml"},
+			failed: true,
+		},
+	}
+	for _, tc := range testCases {
+		fail := UnitTest(tc.files, tc.disableGroupLabel)
+		if fail != tc.failed {
+			t.Fatalf("failed to test %s, expect %t, got %t", tc.name, tc.failed, fail)
+		}
+	}
+}
diff --git a/app/vmalert/README.md b/app/vmalert/README.md
index 26c067e95..f389ce554 100644
--- a/app/vmalert/README.md
+++ b/app/vmalert/README.md
@@ -754,6 +754,11 @@ See full description for these flags in `./vmalert -help`.
 * `limit` group's param has no effect during replay (might be changed in future);
 * `keep_firing_for` alerting rule param has no effect during replay (might be changed in future).
 
+## Unit Testing for Rules
+
+You can use `vmalert-tool` to test your alerting and recording rules like [promtool does](https://prometheus.io/docs/prometheus/latest/configuration/unit_testing_rules/).
+See more details [here](https://docs.victoriametrics.com/vmalert-tool.html#Unit-testing-for-rules).
+
 ## Monitoring
 
 `vmalert` exports various metrics in Prometheus exposition format at `http://vmalert-host:8880/metrics` page.
diff --git a/app/vmalert/datasource/faker.go b/app/vmalert/datasource/faker.go
new file mode 100644
index 000000000..397fc90f6
--- /dev/null
+++ b/app/vmalert/datasource/faker.go
@@ -0,0 +1,131 @@
+package datasource
+
+import (
+	"context"
+	"net/http"
+	"sync"
+	"time"
+)
+
+// FakeQuerier is a mock querier that return predefined results and error message
+type FakeQuerier struct {
+	sync.Mutex
+	metrics []Metric
+	err     error
+}
+
+// SetErr sets query error message
+func (fq *FakeQuerier) SetErr(err error) {
+	fq.Lock()
+	fq.err = err
+	fq.Unlock()
+}
+
+// Reset reset querier's error message and results
+func (fq *FakeQuerier) Reset() {
+	fq.Lock()
+	fq.err = nil
+	fq.metrics = fq.metrics[:0]
+	fq.Unlock()
+}
+
+// Add appends metrics to querier result metrics
+func (fq *FakeQuerier) Add(metrics ...Metric) {
+	fq.Lock()
+	fq.metrics = append(fq.metrics, metrics...)
+	fq.Unlock()
+}
+
+// BuildWithParams return FakeQuerier itself
+func (fq *FakeQuerier) BuildWithParams(_ QuerierParams) Querier {
+	return fq
+}
+
+// QueryRange performs query
+func (fq *FakeQuerier) QueryRange(ctx context.Context, q string, _, _ time.Time) (Result, error) {
+	req, _, err := fq.Query(ctx, q, time.Now())
+	return req, err
+}
+
+// Query returns metrics restored in querier
+func (fq *FakeQuerier) Query(_ context.Context, _ string, _ time.Time) (Result, *http.Request, error) {
+	fq.Lock()
+	defer fq.Unlock()
+	if fq.err != nil {
+		return Result{}, nil, fq.err
+	}
+	cp := make([]Metric, len(fq.metrics))
+	copy(cp, fq.metrics)
+	req, _ := http.NewRequest(http.MethodPost, "foo.com", nil)
+	return Result{Data: cp}, req, nil
+}
+
+// FakeQuerierWithRegistry can store different results for different query expr
+type FakeQuerierWithRegistry struct {
+	sync.Mutex
+	registry map[string][]Metric
+}
+
+// Set stores query result for given key
+func (fqr *FakeQuerierWithRegistry) Set(key string, metrics ...Metric) {
+	fqr.Lock()
+	if fqr.registry == nil {
+		fqr.registry = make(map[string][]Metric)
+	}
+	fqr.registry[key] = metrics
+	fqr.Unlock()
+}
+
+// Reset clean querier's results registry
+func (fqr *FakeQuerierWithRegistry) Reset() {
+	fqr.Lock()
+	fqr.registry = nil
+	fqr.Unlock()
+}
+
+// BuildWithParams returns itself
+func (fqr *FakeQuerierWithRegistry) BuildWithParams(_ QuerierParams) Querier {
+	return fqr
+}
+
+// QueryRange performs query
+func (fqr *FakeQuerierWithRegistry) QueryRange(ctx context.Context, q string, _, _ time.Time) (Result, error) {
+	req, _, err := fqr.Query(ctx, q, time.Now())
+	return req, err
+}
+
+// Query returns metrics restored in querier registry
+func (fqr *FakeQuerierWithRegistry) Query(_ context.Context, expr string, _ time.Time) (Result, *http.Request, error) {
+	fqr.Lock()
+	defer fqr.Unlock()
+
+	req, _ := http.NewRequest(http.MethodPost, "foo.com", nil)
+	metrics, ok := fqr.registry[expr]
+	if !ok {
+		return Result{}, req, nil
+	}
+	cp := make([]Metric, len(metrics))
+	copy(cp, metrics)
+	return Result{Data: cp}, req, nil
+}
+
+// FakeQuerierWithDelay mock querier with given delay duration
+type FakeQuerierWithDelay struct {
+	FakeQuerier
+	Delay time.Duration
+}
+
+// Query returns query result after delay duration
+func (fqd *FakeQuerierWithDelay) Query(ctx context.Context, expr string, ts time.Time) (Result, *http.Request, error) {
+	timer := time.NewTimer(fqd.Delay)
+	select {
+	case <-ctx.Done():
+	case <-timer.C:
+	}
+	return fqd.FakeQuerier.Query(ctx, expr, ts)
+}
+
+// BuildWithParams returns itself
+func (fqd *FakeQuerierWithDelay) BuildWithParams(_ QuerierParams) Querier {
+	return fqd
+}
diff --git a/app/vmalert/main.go b/app/vmalert/main.go
index 8d7dcdc6d..bed190eff 100644
--- a/app/vmalert/main.go
+++ b/app/vmalert/main.go
@@ -18,6 +18,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remoteread"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/templates"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/buildinfo"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/envflag"
@@ -66,11 +67,6 @@ absolute path to all .tpl files in root.
 
 	validateTemplates   = flag.Bool("rule.validateTemplates", true, "Whether to validate annotation and label templates")
 	validateExpressions = flag.Bool("rule.validateExpressions", true, "Whether to validate rules expressions via MetricsQL engine")
-	maxResolveDuration  = flag.Duration("rule.maxResolveDuration", 0, "Limits the maximum duration for automatic alert expiration, "+
-		"which by default is 4 times evaluationInterval of the parent group.")
-	resendDelay            = flag.Duration("rule.resendDelay", 0, "Minimum amount of time to wait before resending an alert to notifier")
-	ruleUpdateEntriesLimit = flag.Int("rule.updateEntriesLimit", 20, "Defines the max number of rule's state updates stored in-memory. "+
-		"Rule's updates are available on rule's Details page and are used for debugging purposes. The number of stored updates can be overridden per rule via update_entries_limit param.")
 
 	externalURL         = flag.String("external.url", "", "External URL is used as alert's source for sent alerts to the notifier. By default, hostname is used as address.")
 	externalAlertSource = flag.String("external.alert.source", "", `External Alert Source allows to override the Source link for alerts sent to AlertManager `+
@@ -82,12 +78,8 @@ absolute path to all .tpl files in root.
 	externalLabels = flagutil.NewArrayString("external.label", "Optional label in the form 'Name=value' to add to all generated recording rules and alerts. "+
 		"Pass multiple -label flags in order to add multiple label sets.")
 
-	remoteReadLookBack = flag.Duration("remoteRead.lookback", time.Hour, "Lookback defines how far to look into past for alerts timeseries."+
-		" For example, if lookback=1h then range from now() to now()-1h will be scanned.")
 	remoteReadIgnoreRestoreErrors = flag.Bool("remoteRead.ignoreRestoreErrors", true, "Whether to ignore errors from remote storage when restoring alerts state on startup. DEPRECATED - this flag has no effect and will be removed in the next releases.")
 
-	disableAlertGroupLabel = flag.Bool("disableAlertgroupLabel", false, "Whether to disable adding group's Name as label to generated alerts and time series.")
-
 	dryRun = flag.Bool("dryRun", false, "Whether to check only config files without running vmalert. The rules file are validated. The -rule flag must be specified.")
 )
 
@@ -229,7 +221,7 @@ func newManager(ctx context.Context) (*manager, error) {
 		return nil, fmt.Errorf("failed to init notifier: %w", err)
 	}
 	manager := &manager{
-		groups:         make(map[uint64]*Group),
+		groups:         make(map[uint64]*rule.Group),
 		querierBuilder: q,
 		notifiers:      nts,
 		labels:         labels,
diff --git a/app/vmalert/main_test.go b/app/vmalert/main_test.go
index afa27bace..5a0377eef 100644
--- a/app/vmalert/main_test.go
+++ b/app/vmalert/main_test.go
@@ -8,11 +8,19 @@ import (
 	"testing"
 	"time"
 
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/procutil"
 )
 
+func init() {
+	// Disable rand sleep on group start during tests in order to speed up test execution.
+	// Rand sleep is needed only in prod code.
+	rule.SkipRandSleepOnGroupStart = true
+}
+
 func TestGetExternalURL(t *testing.T) {
 	expURL := "https://vicotriametrics.com/path"
 	u, err := getExternalURL(expURL, "", false)
@@ -98,10 +106,10 @@ groups:
 	ctx, cancel := context.WithCancel(context.Background())
 
 	m := &manager{
-		querierBuilder: &fakeQuerier{},
-		groups:         make(map[uint64]*Group),
+		querierBuilder: &datasource.FakeQuerier{},
+		groups:         make(map[uint64]*rule.Group),
 		labels:         map[string]string{},
-		notifiers:      func() []notifier.Notifier { return []notifier.Notifier{&fakeNotifier{}} },
+		notifiers:      func() []notifier.Notifier { return []notifier.Notifier{&notifier.FakeNotifier{}} },
 		rw:             &remotewrite.Client{},
 	}
 
diff --git a/app/vmalert/manager.go b/app/vmalert/manager.go
index 26e909ddf..a15b4c97e 100644
--- a/app/vmalert/manager.go
+++ b/app/vmalert/manager.go
@@ -3,14 +3,13 @@ package main
 import (
 	"context"
 	"fmt"
-	"net/url"
-	"sort"
 	"sync"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 )
 
@@ -19,7 +18,7 @@ type manager struct {
 	querierBuilder datasource.QuerierBuilder
 	notifiers      func() []notifier.Notifier
 
-	rw *remotewrite.Client
+	rw remotewrite.RWClient
 	// remote read builder.
 	rr datasource.QuerierBuilder
 
@@ -27,28 +26,28 @@ type manager struct {
 	labels map[string]string
 
 	groupsMu sync.RWMutex
-	groups   map[uint64]*Group
+	groups   map[uint64]*rule.Group
 }
 
-// RuleAPI generates APIRule object from alert by its ID(hash)
-func (m *manager) RuleAPI(gID, rID uint64) (APIRule, error) {
+// ruleAPI generates apiRule object from alert by its ID(hash)
+func (m *manager) ruleAPI(gID, rID uint64) (apiRule, error) {
 	m.groupsMu.RLock()
 	defer m.groupsMu.RUnlock()
 
 	g, ok := m.groups[gID]
 	if !ok {
-		return APIRule{}, fmt.Errorf("can't find group with id %d", gID)
+		return apiRule{}, fmt.Errorf("can't find group with id %d", gID)
 	}
 	for _, rule := range g.Rules {
 		if rule.ID() == rID {
-			return rule.ToAPI(), nil
+			return ruleToAPI(rule), nil
 		}
 	}
-	return APIRule{}, fmt.Errorf("can't find rule with id %d in group %q", rID, g.Name)
+	return apiRule{}, fmt.Errorf("can't find rule with id %d in group %q", rID, g.Name)
 }
 
-// AlertAPI generates APIAlert object from alert by its ID(hash)
-func (m *manager) AlertAPI(gID, aID uint64) (*APIAlert, error) {
+// alertAPI generates apiAlert object from alert by its ID(hash)
+func (m *manager) alertAPI(gID, aID uint64) (*apiAlert, error) {
 	m.groupsMu.RLock()
 	defer m.groupsMu.RUnlock()
 
@@ -56,12 +55,12 @@ func (m *manager) AlertAPI(gID, aID uint64) (*APIAlert, error) {
 	if !ok {
 		return nil, fmt.Errorf("can't find group with id %d", gID)
 	}
-	for _, rule := range g.Rules {
-		ar, ok := rule.(*AlertingRule)
+	for _, r := range g.Rules {
+		ar, ok := r.(*rule.AlertingRule)
 		if !ok {
 			continue
 		}
-		if apiAlert := ar.AlertAPI(aID); apiAlert != nil {
+		if apiAlert := alertToAPI(ar, aID); apiAlert != nil {
 			return apiAlert, nil
 		}
 	}
@@ -82,15 +81,15 @@ func (m *manager) close() {
 	m.wg.Wait()
 }
 
-func (m *manager) startGroup(ctx context.Context, g *Group, restore bool) error {
+func (m *manager) startGroup(ctx context.Context, g *rule.Group, restore bool) error {
 	m.wg.Add(1)
 	id := g.ID()
 	go func() {
 		defer m.wg.Done()
 		if restore {
-			g.start(ctx, m.notifiers, m.rw, m.rr)
+			g.Start(ctx, m.notifiers, m.rw, m.rr)
 		} else {
-			g.start(ctx, m.notifiers, m.rw, nil)
+			g.Start(ctx, m.notifiers, m.rw, nil)
 		}
 	}()
 	m.groups[id] = g
@@ -99,7 +98,7 @@ func (m *manager) startGroup(ctx context.Context, g *Group, restore bool) error
 
 func (m *manager) update(ctx context.Context, groupsCfg []config.Group, restore bool) error {
 	var rrPresent, arPresent bool
-	groupsRegistry := make(map[uint64]*Group)
+	groupsRegistry := make(map[uint64]*rule.Group)
 	for _, cfg := range groupsCfg {
 		for _, r := range cfg.Rules {
 			if rrPresent && arPresent {
@@ -112,7 +111,7 @@ func (m *manager) update(ctx context.Context, groupsCfg []config.Group, restore
 				arPresent = true
 			}
 		}
-		ng := newGroup(cfg, m.querierBuilder, *evaluationInterval, m.labels)
+		ng := rule.NewGroup(cfg, m.querierBuilder, *evaluationInterval, m.labels)
 		groupsRegistry[ng.ID()] = ng
 	}
 
@@ -124,8 +123,8 @@ func (m *manager) update(ctx context.Context, groupsCfg []config.Group, restore
 	}
 
 	type updateItem struct {
-		old *Group
-		new *Group
+		old *rule.Group
+		new *rule.Group
 	}
 	var toUpdate []updateItem
 
@@ -135,7 +134,7 @@ func (m *manager) update(ctx context.Context, groupsCfg []config.Group, restore
 		if !ok {
 			// old group is not present in new list,
 			// so must be stopped and deleted
-			og.close()
+			og.Close()
 			delete(m.groups, og.ID())
 			og = nil
 			continue
@@ -157,81 +156,13 @@ func (m *manager) update(ctx context.Context, groupsCfg []config.Group, restore
 		var wg sync.WaitGroup
 		for _, item := range toUpdate {
 			wg.Add(1)
-			go func(old *Group, new *Group) {
-				old.updateCh <- new
+			go func(old *rule.Group, new *rule.Group) {
+				old.UpdateWith(new)
 				wg.Done()
 			}(item.old, item.new)
-			item.old.interruptEval()
+			item.old.InterruptEval()
 		}
 		wg.Wait()
 	}
 	return nil
 }
-
-func (g *Group) toAPI() APIGroup {
-	g.mu.RLock()
-	defer g.mu.RUnlock()
-
-	ag := APIGroup{
-		// encode as string to avoid rounding
-		ID: fmt.Sprintf("%d", g.ID()),
-
-		Name:            g.Name,
-		Type:            g.Type.String(),
-		File:            g.File,
-		Interval:        g.Interval.Seconds(),
-		LastEvaluation:  g.LastEvaluation,
-		Concurrency:     g.Concurrency,
-		Params:          urlValuesToStrings(g.Params),
-		Headers:         headersToStrings(g.Headers),
-		NotifierHeaders: headersToStrings(g.NotifierHeaders),
-
-		Labels: g.Labels,
-	}
-	ag.Rules = make([]APIRule, 0)
-	for _, r := range g.Rules {
-		ag.Rules = append(ag.Rules, r.ToAPI())
-	}
-	return ag
-}
-
-func urlValuesToStrings(values url.Values) []string {
-	if len(values) < 1 {
-		return nil
-	}
-
-	keys := make([]string, 0, len(values))
-	for k := range values {
-		keys = append(keys, k)
-	}
-	sort.Strings(keys)
-
-	var res []string
-	for _, k := range keys {
-		params := values[k]
-		for _, v := range params {
-			res = append(res, fmt.Sprintf("%s=%s", k, v))
-		}
-	}
-	return res
-}
-
-func headersToStrings(headers map[string]string) []string {
-	if len(headers) < 1 {
-		return nil
-	}
-
-	keys := make([]string, 0, len(headers))
-	for k := range headers {
-		keys = append(keys, k)
-	}
-	sort.Strings(keys)
-
-	var res []string
-	for _, k := range keys {
-		v := headers[k]
-		res = append(res, fmt.Sprintf("%s: %s", k, v))
-	}
-
-	return res
-}
diff --git a/app/vmalert/manager_test.go b/app/vmalert/manager_test.go
index 4c270322f..e5f879796 100644
--- a/app/vmalert/manager_test.go
+++ b/app/vmalert/manager_test.go
@@ -10,8 +10,10 @@ import (
 	"time"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/templates"
 )
 
@@ -26,7 +28,7 @@ func TestMain(m *testing.M) {
 // successful cases of
 // starting with empty rules folder
 func TestManagerEmptyRulesDir(t *testing.T) {
-	m := &manager{groups: make(map[uint64]*Group)}
+	m := &manager{groups: make(map[uint64]*rule.Group)}
 	cfg := loadCfg(t, []string{"foo/bar"}, true, true)
 	if err := m.update(context.Background(), cfg, false); err != nil {
 		t.Fatalf("expected to load successfully with empty rules dir; got err instead: %v", err)
@@ -38,9 +40,9 @@ func TestManagerEmptyRulesDir(t *testing.T) {
 // Should be executed with -race flag
 func TestManagerUpdateConcurrent(t *testing.T) {
 	m := &manager{
-		groups:         make(map[uint64]*Group),
-		querierBuilder: &fakeQuerier{},
-		notifiers:      func() []notifier.Notifier { return []notifier.Notifier{&fakeNotifier{}} },
+		groups:         make(map[uint64]*rule.Group),
+		querierBuilder: &datasource.FakeQuerier{},
+		notifiers:      func() []notifier.Notifier { return []notifier.Notifier{&notifier.FakeNotifier{}} },
 	}
 	paths := []string{
 		"config/testdata/dir/rules0-good.rules",
@@ -91,7 +93,7 @@ func TestManagerUpdate(t *testing.T) {
 	}()
 
 	var (
-		VMRows = &AlertingRule{
+		VMRows = &rule.AlertingRule{
 			Name: "VMRows",
 			Expr: "vm_rows > 0",
 			For:  10 * time.Second,
@@ -104,7 +106,7 @@ func TestManagerUpdate(t *testing.T) {
 				"description": "{{$labels}}",
 			},
 		}
-		Conns = &AlertingRule{
+		Conns = &rule.AlertingRule{
 			Name: "Conns",
 			Expr: "sum(vm_tcplistener_conns) by(instance) > 1",
 			Annotations: map[string]string{
@@ -112,7 +114,7 @@ func TestManagerUpdate(t *testing.T) {
 				"description": "It is {{ $value }} connections for {{$labels.instance}}",
 			},
 		}
-		ExampleAlertAlwaysFiring = &AlertingRule{
+		ExampleAlertAlwaysFiring = &rule.AlertingRule{
 			Name: "ExampleAlertAlwaysFiring",
 			Expr: "sum by(job) (up == 1)",
 		}
@@ -122,20 +124,20 @@ func TestManagerUpdate(t *testing.T) {
 		name       string
 		initPath   string
 		updatePath string
-		want       []*Group
+		want       []*rule.Group
 	}{
 		{
 			name:       "update good rules",
 			initPath:   "config/testdata/rules/rules0-good.rules",
 			updatePath: "config/testdata/dir/rules1-good.rules",
-			want: []*Group{
+			want: []*rule.Group{
 				{
 					File:     "config/testdata/dir/rules1-good.rules",
 					Name:     "duplicatedGroupDiffFiles",
 					Type:     config.NewPrometheusType(),
 					Interval: defaultEvalInterval,
-					Rules: []Rule{
-						&AlertingRule{
+					Rules: []rule.Rule{
+						&rule.AlertingRule{
 							Name:   "VMRows",
 							Expr:   "vm_rows > 0",
 							For:    5 * time.Minute,
@@ -153,19 +155,20 @@ func TestManagerUpdate(t *testing.T) {
 			name:       "update good rules from 1 to 2 groups",
 			initPath:   "config/testdata/dir/rules/rules1-good.rules",
 			updatePath: "config/testdata/rules/rules0-good.rules",
-			want: []*Group{
+			want: []*rule.Group{
 				{
 					File:     "config/testdata/rules/rules0-good.rules",
 					Name:     "groupGorSingleAlert",
 					Type:     config.NewPrometheusType(),
-					Rules:    []Rule{VMRows},
 					Interval: defaultEvalInterval,
+					Rules:    []rule.Rule{VMRows},
 				},
 				{
 					File:     "config/testdata/rules/rules0-good.rules",
 					Interval: defaultEvalInterval,
 					Type:     config.NewPrometheusType(),
-					Name:     "TestGroup", Rules: []Rule{
+					Name:     "TestGroup",
+					Rules: []rule.Rule{
 						Conns,
 						ExampleAlertAlwaysFiring,
 					},
@@ -176,20 +179,20 @@ func TestManagerUpdate(t *testing.T) {
 			name:       "update with one bad rule file",
 			initPath:   "config/testdata/rules/rules0-good.rules",
 			updatePath: "config/testdata/dir/rules2-bad.rules",
-			want: []*Group{
+			want: []*rule.Group{
 				{
 					File:     "config/testdata/rules/rules0-good.rules",
 					Name:     "groupGorSingleAlert",
 					Type:     config.NewPrometheusType(),
 					Interval: defaultEvalInterval,
-					Rules:    []Rule{VMRows},
+					Rules:    []rule.Rule{VMRows},
 				},
 				{
 					File:     "config/testdata/rules/rules0-good.rules",
 					Interval: defaultEvalInterval,
 					Name:     "TestGroup",
 					Type:     config.NewPrometheusType(),
-					Rules: []Rule{
+					Rules: []rule.Rule{
 						Conns,
 						ExampleAlertAlwaysFiring,
 					},
@@ -200,19 +203,20 @@ func TestManagerUpdate(t *testing.T) {
 			name:       "update empty dir rules from 0 to 2 groups",
 			initPath:   "config/testdata/empty/*",
 			updatePath: "config/testdata/rules/rules0-good.rules",
-			want: []*Group{
+			want: []*rule.Group{
 				{
 					File:     "config/testdata/rules/rules0-good.rules",
 					Name:     "groupGorSingleAlert",
 					Type:     config.NewPrometheusType(),
 					Interval: defaultEvalInterval,
-					Rules:    []Rule{VMRows},
+					Rules:    []rule.Rule{VMRows},
 				},
 				{
 					File:     "config/testdata/rules/rules0-good.rules",
 					Interval: defaultEvalInterval,
 					Type:     config.NewPrometheusType(),
-					Name:     "TestGroup", Rules: []Rule{
+					Name:     "TestGroup",
+					Rules: []rule.Rule{
 						Conns,
 						ExampleAlertAlwaysFiring,
 					},
@@ -224,9 +228,9 @@ func TestManagerUpdate(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			ctx, cancel := context.WithCancel(context.TODO())
 			m := &manager{
-				groups:         make(map[uint64]*Group),
-				querierBuilder: &fakeQuerier{},
-				notifiers:      func() []notifier.Notifier { return []notifier.Notifier{&fakeNotifier{}} },
+				groups:         make(map[uint64]*rule.Group),
+				querierBuilder: &datasource.FakeQuerier{},
+				notifiers:      func() []notifier.Notifier { return []notifier.Notifier{&notifier.FakeNotifier{}} },
 			}
 
 			cfgInit := loadCfg(t, []string{tc.initPath}, true, true)
@@ -255,11 +259,36 @@ func TestManagerUpdate(t *testing.T) {
 		})
 	}
 }
+func compareGroups(t *testing.T, a, b *rule.Group) {
+	t.Helper()
+	if a.Name != b.Name {
+		t.Fatalf("expected group name %q; got %q", a.Name, b.Name)
+	}
+	if a.File != b.File {
+		t.Fatalf("expected group %q file name %q; got %q", a.Name, a.File, b.File)
+	}
+	if a.Interval != b.Interval {
+		t.Fatalf("expected group %q interval %v; got %v", a.Name, a.Interval, b.Interval)
+	}
+	if len(a.Rules) != len(b.Rules) {
+		t.Fatalf("expected group %s to have %d rules; got: %d",
+			a.Name, len(a.Rules), len(b.Rules))
+	}
+	for i, r := range a.Rules {
+		got, want := r, b.Rules[i]
+		if a.ID() != b.ID() {
+			t.Fatalf("expected to have rule %q; got %q", want.ID(), got.ID())
+		}
+		if err := rule.CompareRules(t, want, got); err != nil {
+			t.Fatalf("comparison error: %s", err)
+		}
+	}
+}
 
 func TestManagerUpdateNegative(t *testing.T) {
 	testCases := []struct {
 		notifiers []notifier.Notifier
-		rw        *remotewrite.Client
+		rw        remotewrite.RWClient
 		cfg       config.Group
 		expErr    string
 	}{
@@ -286,7 +315,7 @@ func TestManagerUpdateNegative(t *testing.T) {
 			"contains alerting rules",
 		},
 		{
-			[]notifier.Notifier{&fakeNotifier{}},
+			[]notifier.Notifier{&notifier.FakeNotifier{}},
 			nil,
 			config.Group{
 				Name: "Recording and alerting rules",
@@ -316,8 +345,8 @@ func TestManagerUpdateNegative(t *testing.T) {
 	for _, tc := range testCases {
 		t.Run(tc.cfg.Name, func(t *testing.T) {
 			m := &manager{
-				groups:         make(map[uint64]*Group),
-				querierBuilder: &fakeQuerier{},
+				groups:         make(map[uint64]*rule.Group),
+				querierBuilder: &datasource.FakeQuerier{},
 				rw:             tc.rw,
 			}
 			if tc.notifiers != nil {
@@ -346,21 +375,3 @@ func loadCfg(t *testing.T, path []string, validateAnnotations, validateExpressio
 	}
 	return cfg
 }
-
-func TestUrlValuesToStrings(t *testing.T) {
-	mapQueryParams := map[string][]string{
-		"param1": {"param1"},
-		"param2": {"anotherparam"},
-	}
-	expectedRes := []string{"param1=param1", "param2=anotherparam"}
-	res := urlValuesToStrings(mapQueryParams)
-
-	if len(res) != len(expectedRes) {
-		t.Errorf("Expected length %d, but got %d", len(expectedRes), len(res))
-	}
-	for ind, val := range expectedRes {
-		if val != res[ind] {
-			t.Errorf("Expected %v; but got %v", val, res[ind])
-		}
-	}
-}
diff --git a/app/vmalert/notifier/faker.go b/app/vmalert/notifier/faker.go
new file mode 100644
index 000000000..3fc48a94a
--- /dev/null
+++ b/app/vmalert/notifier/faker.go
@@ -0,0 +1,59 @@
+package notifier
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"time"
+)
+
+// FakeNotifier is a mock notifier
+type FakeNotifier struct {
+	sync.Mutex
+	alerts []Alert
+	// records number of received alerts in total
+	counter int
+}
+
+// Close does nothing
+func (*FakeNotifier) Close() {}
+
+// Addr returns ""
+func (*FakeNotifier) Addr() string { return "" }
+
+// Send sets alerts and increases counter
+func (fn *FakeNotifier) Send(_ context.Context, alerts []Alert, _ map[string]string) error {
+	fn.Lock()
+	defer fn.Unlock()
+	fn.counter += len(alerts)
+	fn.alerts = alerts
+	return nil
+}
+
+// GetCounter returns received alerts count
+func (fn *FakeNotifier) GetCounter() int {
+	fn.Lock()
+	defer fn.Unlock()
+	return fn.counter
+}
+
+// GetAlerts returns stored alerts
+func (fn *FakeNotifier) GetAlerts() []Alert {
+	fn.Lock()
+	defer fn.Unlock()
+	return fn.alerts
+}
+
+// FaultyNotifier is a mock notifier that Send() will return failed response
+type FaultyNotifier struct {
+	FakeNotifier
+}
+
+// Send returns failed response
+func (fn *FaultyNotifier) Send(ctx context.Context, _ []Alert, _ map[string]string) error {
+	d, ok := ctx.Deadline()
+	if ok {
+		time.Sleep(time.Until(d))
+	}
+	return fmt.Errorf("send failed")
+}
diff --git a/app/vmalert/remotewrite/client.go b/app/vmalert/remotewrite/client.go
new file mode 100644
index 000000000..2fcdcbf16
--- /dev/null
+++ b/app/vmalert/remotewrite/client.go
@@ -0,0 +1,322 @@
+package remotewrite
+
+import (
+	"bytes"
+	"context"
+	"flag"
+	"fmt"
+	"io"
+	"net/http"
+	"path"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/golang/snappy"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promauth"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
+	"github.com/VictoriaMetrics/metrics"
+)
+
+const (
+	defaultConcurrency   = 4
+	defaultMaxBatchSize  = 1e3
+	defaultMaxQueueSize  = 1e5
+	defaultFlushInterval = 5 * time.Second
+	defaultWriteTimeout  = 30 * time.Second
+)
+
+var (
+	disablePathAppend = flag.Bool("remoteWrite.disablePathAppend", false, "Whether to disable automatic appending of '/api/v1/write' path to the configured -remoteWrite.url.")
+	sendTimeout       = flag.Duration("remoteWrite.sendTimeout", 30*time.Second, "Timeout for sending data to the configured -remoteWrite.url.")
+	retryMinInterval  = flag.Duration("remoteWrite.retryMinInterval", time.Second, "The minimum delay between retry attempts. Every next retry attempt will double the delay to prevent hammering of remote database. See also -remoteWrite.retryMaxInterval")
+	retryMaxTime      = flag.Duration("remoteWrite.retryMaxTime", time.Second*30, "The max time spent on retry attempts for the failed remote-write request. Change this value if it is expected for remoteWrite.url to be unreachable for more than -remoteWrite.retryMaxTime. See also -remoteWrite.retryMinInterval")
+)
+
+// Client is an asynchronous HTTP client for writing
+// timeseries via remote write protocol.
+type Client struct {
+	addr          string
+	c             *http.Client
+	authCfg       *promauth.Config
+	input         chan prompbmarshal.TimeSeries
+	flushInterval time.Duration
+	maxBatchSize  int
+	maxQueueSize  int
+
+	wg     sync.WaitGroup
+	doneCh chan struct{}
+}
+
+// Config is config for remote write client.
+type Config struct {
+	// Addr of remote storage
+	Addr    string
+	AuthCfg *promauth.Config
+
+	// Concurrency defines number of readers that
+	// concurrently read from the queue and flush data
+	Concurrency int
+	// MaxBatchSize defines max number of timeseries
+	// to be flushed at once
+	MaxBatchSize int
+	// MaxQueueSize defines max length of input queue
+	// populated by Push method.
+	// Push will be rejected once queue is full.
+	MaxQueueSize int
+	// FlushInterval defines time interval for flushing batches
+	FlushInterval time.Duration
+	// Transport will be used by the underlying http.Client
+	Transport *http.Transport
+}
+
+// NewClient returns asynchronous client for
+// writing timeseries via remotewrite protocol.
+func NewClient(ctx context.Context, cfg Config) (*Client, error) {
+	if cfg.Addr == "" {
+		return nil, fmt.Errorf("config.Addr can't be empty")
+	}
+	if cfg.MaxBatchSize == 0 {
+		cfg.MaxBatchSize = defaultMaxBatchSize
+	}
+	if cfg.MaxQueueSize == 0 {
+		cfg.MaxQueueSize = defaultMaxQueueSize
+	}
+	if cfg.FlushInterval == 0 {
+		cfg.FlushInterval = defaultFlushInterval
+	}
+	if cfg.Transport == nil {
+		cfg.Transport = http.DefaultTransport.(*http.Transport).Clone()
+	}
+	cc := defaultConcurrency
+	if cfg.Concurrency > 0 {
+		cc = cfg.Concurrency
+	}
+	c := &Client{
+		c: &http.Client{
+			Timeout:   *sendTimeout,
+			Transport: cfg.Transport,
+		},
+		addr:          strings.TrimSuffix(cfg.Addr, "/"),
+		authCfg:       cfg.AuthCfg,
+		flushInterval: cfg.FlushInterval,
+		maxBatchSize:  cfg.MaxBatchSize,
+		maxQueueSize:  cfg.MaxQueueSize,
+		doneCh:        make(chan struct{}),
+		input:         make(chan prompbmarshal.TimeSeries, cfg.MaxQueueSize),
+	}
+
+	for i := 0; i < cc; i++ {
+		c.run(ctx)
+	}
+	return c, nil
+}
+
+// Push adds timeseries into queue for writing into remote storage.
+// Push returns and error if client is stopped or if queue is full.
+func (c *Client) Push(s prompbmarshal.TimeSeries) error {
+	select {
+	case <-c.doneCh:
+		return fmt.Errorf("client is closed")
+	case c.input <- s:
+		return nil
+	default:
+		return fmt.Errorf("failed to push timeseries - queue is full (%d entries). "+
+			"Queue size is controlled by -remoteWrite.maxQueueSize flag",
+			c.maxQueueSize)
+	}
+}
+
+// Close stops the client and waits for all goroutines
+// to exit.
+func (c *Client) Close() error {
+	if c.doneCh == nil {
+		return fmt.Errorf("client is already closed")
+	}
+	close(c.input)
+	close(c.doneCh)
+	c.wg.Wait()
+	return nil
+}
+
+func (c *Client) run(ctx context.Context) {
+	ticker := time.NewTicker(c.flushInterval)
+	wr := &prompbmarshal.WriteRequest{}
+	shutdown := func() {
+		for ts := range c.input {
+			wr.Timeseries = append(wr.Timeseries, ts)
+		}
+		lastCtx, cancel := context.WithTimeout(context.Background(), defaultWriteTimeout)
+		logger.Infof("shutting down remote write client and flushing remained %d series", len(wr.Timeseries))
+		c.flush(lastCtx, wr)
+		cancel()
+	}
+	c.wg.Add(1)
+	go func() {
+		defer c.wg.Done()
+		defer ticker.Stop()
+		for {
+			select {
+			case <-c.doneCh:
+				shutdown()
+				return
+			case <-ctx.Done():
+				shutdown()
+				return
+			case <-ticker.C:
+				c.flush(ctx, wr)
+			case ts, ok := <-c.input:
+				if !ok {
+					continue
+				}
+				wr.Timeseries = append(wr.Timeseries, ts)
+				if len(wr.Timeseries) >= c.maxBatchSize {
+					c.flush(ctx, wr)
+				}
+			}
+		}
+	}()
+}
+
+var (
+	sentRows            = metrics.NewCounter(`vmalert_remotewrite_sent_rows_total`)
+	sentBytes           = metrics.NewCounter(`vmalert_remotewrite_sent_bytes_total`)
+	sendDuration        = metrics.NewFloatCounter(`vmalert_remotewrite_send_duration_seconds_total`)
+	droppedRows         = metrics.NewCounter(`vmalert_remotewrite_dropped_rows_total`)
+	droppedBytes        = metrics.NewCounter(`vmalert_remotewrite_dropped_bytes_total`)
+	bufferFlushDuration = metrics.NewHistogram(`vmalert_remotewrite_flush_duration_seconds`)
+
+	_ = metrics.NewGauge(`vmalert_remotewrite_concurrency`, func() float64 {
+		return float64(*concurrency)
+	})
+)
+
+// flush is a blocking function that marshals WriteRequest and sends
+// it to remote-write endpoint. Flush performs limited amount of retries
+// if request fails.
+func (c *Client) flush(ctx context.Context, wr *prompbmarshal.WriteRequest) {
+	if len(wr.Timeseries) < 1 {
+		return
+	}
+	defer prompbmarshal.ResetWriteRequest(wr)
+	defer bufferFlushDuration.UpdateDuration(time.Now())
+
+	data, err := wr.Marshal()
+	if err != nil {
+		logger.Errorf("failed to marshal WriteRequest: %s", err)
+		return
+	}
+
+	b := snappy.Encode(nil, data)
+
+	retryInterval, maxRetryInterval := *retryMinInterval, *retryMaxTime
+	if retryInterval > maxRetryInterval {
+		retryInterval = maxRetryInterval
+	}
+	timeStart := time.Now()
+	defer func() {
+		sendDuration.Add(time.Since(timeStart).Seconds())
+	}()
+L:
+	for attempts := 0; ; attempts++ {
+		err := c.send(ctx, b)
+		if err == nil {
+			sentRows.Add(len(wr.Timeseries))
+			sentBytes.Add(len(b))
+			return
+		}
+
+		_, isNotRetriable := err.(*nonRetriableError)
+		logger.Warnf("attempt %d to send request failed: %s (retriable: %v)", attempts+1, err, !isNotRetriable)
+
+		if isNotRetriable {
+			// exit fast if error isn't retriable
+			break
+		}
+
+		// check if request has been cancelled before backoff
+		select {
+		case <-ctx.Done():
+			logger.Errorf("interrupting retry attempt %d: context cancelled", attempts+1)
+			break L
+		default:
+		}
+
+		timeLeftForRetries := maxRetryInterval - time.Since(timeStart)
+		if timeLeftForRetries < 0 {
+			// the max retry time has passed, so we give up
+			break
+		}
+
+		if retryInterval > timeLeftForRetries {
+			retryInterval = timeLeftForRetries
+		}
+		// sleeping to prevent remote db hammering
+		time.Sleep(retryInterval)
+		retryInterval *= 2
+
+	}
+
+	droppedRows.Add(len(wr.Timeseries))
+	droppedBytes.Add(len(b))
+	logger.Errorf("attempts to send remote-write request failed - dropping %d time series",
+		len(wr.Timeseries))
+}
+
+func (c *Client) send(ctx context.Context, data []byte) error {
+	r := bytes.NewReader(data)
+	req, err := http.NewRequest(http.MethodPost, c.addr, r)
+	if err != nil {
+		return fmt.Errorf("failed to create new HTTP request: %w", err)
+	}
+
+	// RFC standard compliant headers
+	req.Header.Set("Content-Encoding", "snappy")
+	req.Header.Set("Content-Type", "application/x-protobuf")
+
+	// Prometheus compliant headers
+	req.Header.Set("X-Prometheus-Remote-Write-Version", "0.1.0")
+
+	if c.authCfg != nil {
+		c.authCfg.SetHeaders(req, true)
+	}
+	if !*disablePathAppend {
+		req.URL.Path = path.Join(req.URL.Path, "/api/v1/write")
+	}
+	resp, err := c.c.Do(req.WithContext(ctx))
+	if err != nil {
+		return fmt.Errorf("error while sending request to %s: %w; Data len %d(%d)",
+			req.URL.Redacted(), err, len(data), r.Size())
+	}
+	defer func() { _ = resp.Body.Close() }()
+
+	body, _ := io.ReadAll(resp.Body)
+
+	// according to https://prometheus.io/docs/concepts/remote_write_spec/
+	// Prometheus remote Write compatible receivers MUST
+	switch resp.StatusCode / 100 {
+	case 2:
+		// respond with a HTTP 2xx status code when the write is successful.
+		return nil
+	case 4:
+		if resp.StatusCode != http.StatusTooManyRequests {
+			// MUST NOT retry write requests on HTTP 4xx responses other than 429
+			return &nonRetriableError{fmt.Errorf("unexpected response code %d for %s. Response body %q",
+				resp.StatusCode, req.URL.Redacted(), body)}
+		}
+		fallthrough
+	default:
+		return fmt.Errorf("unexpected response code %d for %s. Response body %q",
+			resp.StatusCode, req.URL.Redacted(), body)
+	}
+}
+
+type nonRetriableError struct {
+	err error
+}
+
+func (e *nonRetriableError) Error() string {
+	return e.err.Error()
+}
diff --git a/app/vmalert/remotewrite/remotewrite_test.go b/app/vmalert/remotewrite/client_test.go
similarity index 100%
rename from app/vmalert/remotewrite/remotewrite_test.go
rename to app/vmalert/remotewrite/client_test.go
diff --git a/app/vmalert/remotewrite/debug_client.go b/app/vmalert/remotewrite/debug_client.go
new file mode 100644
index 000000000..a3cd17282
--- /dev/null
+++ b/app/vmalert/remotewrite/debug_client.go
@@ -0,0 +1,97 @@
+package remotewrite
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/http"
+	"path"
+	"strings"
+	"sync"
+
+	"github.com/golang/snappy"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/utils"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
+)
+
+// DebugClient won't push series periodically, but will write data to remote endpoint
+// immediately when Push() is called
+type DebugClient struct {
+	addr string
+	c    *http.Client
+
+	wg sync.WaitGroup
+}
+
+// NewDebugClient initiates and returns a new DebugClient
+func NewDebugClient() (*DebugClient, error) {
+	if *addr == "" {
+		return nil, nil
+	}
+
+	t, err := utils.Transport(*addr, *tlsCertFile, *tlsKeyFile, *tlsCAFile, *tlsServerName, *tlsInsecureSkipVerify)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create transport: %w", err)
+	}
+	c := &DebugClient{
+		c: &http.Client{
+			Timeout:   *sendTimeout,
+			Transport: t,
+		},
+		addr: strings.TrimSuffix(*addr, "/"),
+	}
+	return c, nil
+}
+
+// Push sends the given timeseries to the remote storage.
+func (c *DebugClient) Push(s prompbmarshal.TimeSeries) error {
+	c.wg.Add(1)
+	defer c.wg.Done()
+	wr := &prompbmarshal.WriteRequest{Timeseries: []prompbmarshal.TimeSeries{s}}
+	data, err := wr.Marshal()
+	if err != nil {
+		return fmt.Errorf("failed to marshal the given time series: %w", err)
+	}
+
+	return c.send(data)
+}
+
+// Close stops the DebugClient
+func (c *DebugClient) Close() error {
+	c.wg.Wait()
+	return nil
+}
+
+func (c *DebugClient) send(data []byte) error {
+	b := snappy.Encode(nil, data)
+	r := bytes.NewReader(b)
+	req, err := http.NewRequest(http.MethodPost, c.addr, r)
+	if err != nil {
+		return fmt.Errorf("failed to create new HTTP request: %w", err)
+	}
+
+	// RFC standard compliant headers
+	req.Header.Set("Content-Encoding", "snappy")
+	req.Header.Set("Content-Type", "application/x-protobuf")
+
+	// Prometheus compliant headers
+	req.Header.Set("X-Prometheus-Remote-Write-Version", "0.1.0")
+
+	if !*disablePathAppend {
+		req.URL.Path = path.Join(req.URL.Path, "/api/v1/write")
+	}
+	resp, err := c.c.Do(req)
+	if err != nil {
+		return fmt.Errorf("error while sending request to %s: %w; Data len %d(%d)",
+			req.URL.Redacted(), err, len(data), r.Size())
+	}
+	defer func() { _ = resp.Body.Close() }()
+
+	if resp.StatusCode/100 == 2 {
+		return nil
+	}
+	body, _ := io.ReadAll(resp.Body)
+	return fmt.Errorf("unexpected response code %d for %s. Response body %q",
+		resp.StatusCode, req.URL.Redacted(), body)
+}
diff --git a/app/vmalert/remotewrite/debug_client_test.go b/app/vmalert/remotewrite/debug_client_test.go
new file mode 100644
index 000000000..40c498cbe
--- /dev/null
+++ b/app/vmalert/remotewrite/debug_client_test.go
@@ -0,0 +1,50 @@
+package remotewrite
+
+import (
+	"testing"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
+)
+
+func TestDebugClient_Push(t *testing.T) {
+	testSrv := newRWServer()
+	oldAddr := *addr
+	*addr = testSrv.URL
+	defer func() {
+		*addr = oldAddr
+	}()
+
+	client, err := NewDebugClient()
+	if err != nil {
+		t.Fatalf("failed to create debug client: %s", err)
+	}
+
+	const rowsN = 100
+	var sent int
+	for i := 0; i < rowsN; i++ {
+		s := prompbmarshal.TimeSeries{
+			Samples: []prompbmarshal.Sample{{
+				Value:     float64(i),
+				Timestamp: time.Now().Unix(),
+			}},
+		}
+		err := client.Push(s)
+		if err != nil {
+			t.Fatalf("unexpected err: %s", err)
+		}
+		if err == nil {
+			sent++
+		}
+	}
+	if sent == 0 {
+		t.Fatalf("0 series sent")
+	}
+	if err := client.Close(); err != nil {
+		t.Fatalf("failed to close client: %s", err)
+	}
+	got := testSrv.accepted()
+	if got != sent {
+		t.Fatalf("expected to have %d series; got %d", sent, got)
+	}
+}
diff --git a/app/vmalert/remotewrite/remotewrite.go b/app/vmalert/remotewrite/remotewrite.go
index f217bd78b..27d505e48 100644
--- a/app/vmalert/remotewrite/remotewrite.go
+++ b/app/vmalert/remotewrite/remotewrite.go
@@ -1,322 +1,13 @@
 package remotewrite
 
 import (
-	"bytes"
-	"context"
-	"flag"
-	"fmt"
-	"io"
-	"net/http"
-	"path"
-	"strings"
-	"sync"
-	"time"
-
-	"github.com/golang/snappy"
-
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promauth"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
-	"github.com/VictoriaMetrics/metrics"
 )
 
-var (
-	disablePathAppend = flag.Bool("remoteWrite.disablePathAppend", false, "Whether to disable automatic appending of '/api/v1/write' path to the configured -remoteWrite.url.")
-	sendTimeout       = flag.Duration("remoteWrite.sendTimeout", 30*time.Second, "Timeout for sending data to the configured -remoteWrite.url.")
-	retryMinInterval  = flag.Duration("remoteWrite.retryMinInterval", time.Second, "The minimum delay between retry attempts. Every next retry attempt will double the delay to prevent hammering of remote database. See also -remoteWrite.retryMaxInterval")
-	retryMaxTime      = flag.Duration("remoteWrite.retryMaxTime", time.Second*30, "The max time spent on retry attempts for the failed remote-write request. Change this value if it is expected for remoteWrite.url to be unreachable for more than -remoteWrite.retryMaxTime. See also -remoteWrite.retryMinInterval")
-)
-
-// Client is an asynchronous HTTP client for writing
-// timeseries via remote write protocol.
-type Client struct {
-	addr          string
-	c             *http.Client
-	authCfg       *promauth.Config
-	input         chan prompbmarshal.TimeSeries
-	flushInterval time.Duration
-	maxBatchSize  int
-	maxQueueSize  int
-
-	wg     sync.WaitGroup
-	doneCh chan struct{}
-}
-
-// Config is config for remote write.
-type Config struct {
-	// Addr of remote storage
-	Addr    string
-	AuthCfg *promauth.Config
-
-	// Concurrency defines number of readers that
-	// concurrently read from the queue and flush data
-	Concurrency int
-	// MaxBatchSize defines max number of timeseries
-	// to be flushed at once
-	MaxBatchSize int
-	// MaxQueueSize defines max length of input queue
-	// populated by Push method.
-	// Push will be rejected once queue is full.
-	MaxQueueSize int
-	// FlushInterval defines time interval for flushing batches
-	FlushInterval time.Duration
-	// Transport will be used by the underlying http.Client
-	Transport *http.Transport
-}
-
-const (
-	defaultConcurrency   = 4
-	defaultMaxBatchSize  = 1e3
-	defaultMaxQueueSize  = 1e5
-	defaultFlushInterval = 5 * time.Second
-	defaultWriteTimeout  = 30 * time.Second
-)
-
-// NewClient returns asynchronous client for
-// writing timeseries via remotewrite protocol.
-func NewClient(ctx context.Context, cfg Config) (*Client, error) {
-	if cfg.Addr == "" {
-		return nil, fmt.Errorf("config.Addr can't be empty")
-	}
-	if cfg.MaxBatchSize == 0 {
-		cfg.MaxBatchSize = defaultMaxBatchSize
-	}
-	if cfg.MaxQueueSize == 0 {
-		cfg.MaxQueueSize = defaultMaxQueueSize
-	}
-	if cfg.FlushInterval == 0 {
-		cfg.FlushInterval = defaultFlushInterval
-	}
-	if cfg.Transport == nil {
-		cfg.Transport = http.DefaultTransport.(*http.Transport).Clone()
-	}
-	cc := defaultConcurrency
-	if cfg.Concurrency > 0 {
-		cc = cfg.Concurrency
-	}
-	c := &Client{
-		c: &http.Client{
-			Timeout:   *sendTimeout,
-			Transport: cfg.Transport,
-		},
-		addr:          strings.TrimSuffix(cfg.Addr, "/"),
-		authCfg:       cfg.AuthCfg,
-		flushInterval: cfg.FlushInterval,
-		maxBatchSize:  cfg.MaxBatchSize,
-		maxQueueSize:  cfg.MaxQueueSize,
-		doneCh:        make(chan struct{}),
-		input:         make(chan prompbmarshal.TimeSeries, cfg.MaxQueueSize),
-	}
-
-	for i := 0; i < cc; i++ {
-		c.run(ctx)
-	}
-	return c, nil
-}
-
-// Push adds timeseries into queue for writing into remote storage.
-// Push returns and error if client is stopped or if queue is full.
-func (c *Client) Push(s prompbmarshal.TimeSeries) error {
-	select {
-	case <-c.doneCh:
-		return fmt.Errorf("client is closed")
-	case c.input <- s:
-		return nil
-	default:
-		return fmt.Errorf("failed to push timeseries - queue is full (%d entries). "+
-			"Queue size is controlled by -remoteWrite.maxQueueSize flag",
-			c.maxQueueSize)
-	}
-}
-
-// Close stops the client and waits for all goroutines
-// to exit.
-func (c *Client) Close() error {
-	if c.doneCh == nil {
-		return fmt.Errorf("client is already closed")
-	}
-	close(c.input)
-	close(c.doneCh)
-	c.wg.Wait()
-	return nil
-}
-
-func (c *Client) run(ctx context.Context) {
-	ticker := time.NewTicker(c.flushInterval)
-	wr := &prompbmarshal.WriteRequest{}
-	shutdown := func() {
-		for ts := range c.input {
-			wr.Timeseries = append(wr.Timeseries, ts)
-		}
-		lastCtx, cancel := context.WithTimeout(context.Background(), defaultWriteTimeout)
-		logger.Infof("shutting down remote write client and flushing remained %d series", len(wr.Timeseries))
-		c.flush(lastCtx, wr)
-		cancel()
-	}
-	c.wg.Add(1)
-	go func() {
-		defer c.wg.Done()
-		defer ticker.Stop()
-		for {
-			select {
-			case <-c.doneCh:
-				shutdown()
-				return
-			case <-ctx.Done():
-				shutdown()
-				return
-			case <-ticker.C:
-				c.flush(ctx, wr)
-			case ts, ok := <-c.input:
-				if !ok {
-					continue
-				}
-				wr.Timeseries = append(wr.Timeseries, ts)
-				if len(wr.Timeseries) >= c.maxBatchSize {
-					c.flush(ctx, wr)
-				}
-			}
-		}
-	}()
-}
-
-var (
-	sentRows            = metrics.NewCounter(`vmalert_remotewrite_sent_rows_total`)
-	sentBytes           = metrics.NewCounter(`vmalert_remotewrite_sent_bytes_total`)
-	sendDuration        = metrics.NewFloatCounter(`vmalert_remotewrite_send_duration_seconds_total`)
-	droppedRows         = metrics.NewCounter(`vmalert_remotewrite_dropped_rows_total`)
-	droppedBytes        = metrics.NewCounter(`vmalert_remotewrite_dropped_bytes_total`)
-	bufferFlushDuration = metrics.NewHistogram(`vmalert_remotewrite_flush_duration_seconds`)
-
-	_ = metrics.NewGauge(`vmalert_remotewrite_concurrency`, func() float64 {
-		return float64(*concurrency)
-	})
-)
-
-// flush is a blocking function that marshals WriteRequest and sends
-// it to remote-write endpoint. Flush performs limited amount of retries
-// if request fails.
-func (c *Client) flush(ctx context.Context, wr *prompbmarshal.WriteRequest) {
-	if len(wr.Timeseries) < 1 {
-		return
-	}
-	defer prompbmarshal.ResetWriteRequest(wr)
-	defer bufferFlushDuration.UpdateDuration(time.Now())
-
-	data, err := wr.Marshal()
-	if err != nil {
-		logger.Errorf("failed to marshal WriteRequest: %s", err)
-		return
-	}
-
-	b := snappy.Encode(nil, data)
-
-	retryInterval, maxRetryInterval := *retryMinInterval, *retryMaxTime
-	if retryInterval > maxRetryInterval {
-		retryInterval = maxRetryInterval
-	}
-	timeStart := time.Now()
-	defer func() {
-		sendDuration.Add(time.Since(timeStart).Seconds())
-	}()
-L:
-	for attempts := 0; ; attempts++ {
-		err := c.send(ctx, b)
-		if err == nil {
-			sentRows.Add(len(wr.Timeseries))
-			sentBytes.Add(len(b))
-			return
-		}
-
-		_, isNotRetriable := err.(*nonRetriableError)
-		logger.Warnf("attempt %d to send request failed: %s (retriable: %v)", attempts+1, err, !isNotRetriable)
-
-		if isNotRetriable {
-			// exit fast if error isn't retriable
-			break
-		}
-
-		// check if request has been cancelled before backoff
-		select {
-		case <-ctx.Done():
-			logger.Errorf("interrupting retry attempt %d: context cancelled", attempts+1)
-			break L
-		default:
-		}
-
-		timeLeftForRetries := maxRetryInterval - time.Since(timeStart)
-		if timeLeftForRetries < 0 {
-			// the max retry time has passed, so we give up
-			break
-		}
-
-		if retryInterval > timeLeftForRetries {
-			retryInterval = timeLeftForRetries
-		}
-		// sleeping to prevent remote db hammering
-		time.Sleep(retryInterval)
-		retryInterval *= 2
-
-	}
-
-	droppedRows.Add(len(wr.Timeseries))
-	droppedBytes.Add(len(b))
-	logger.Errorf("attempts to send remote-write request failed - dropping %d time series",
-		len(wr.Timeseries))
-}
-
-func (c *Client) send(ctx context.Context, data []byte) error {
-	r := bytes.NewReader(data)
-	req, err := http.NewRequest(http.MethodPost, c.addr, r)
-	if err != nil {
-		return fmt.Errorf("failed to create new HTTP request: %w", err)
-	}
-
-	// RFC standard compliant headers
-	req.Header.Set("Content-Encoding", "snappy")
-	req.Header.Set("Content-Type", "application/x-protobuf")
-
-	// Prometheus compliant headers
-	req.Header.Set("X-Prometheus-Remote-Write-Version", "0.1.0")
-
-	if c.authCfg != nil {
-		c.authCfg.SetHeaders(req, true)
-	}
-	if !*disablePathAppend {
-		req.URL.Path = path.Join(req.URL.Path, "/api/v1/write")
-	}
-	resp, err := c.c.Do(req.WithContext(ctx))
-	if err != nil {
-		return fmt.Errorf("error while sending request to %s: %w; Data len %d(%d)",
-			req.URL.Redacted(), err, len(data), r.Size())
-	}
-	defer func() { _ = resp.Body.Close() }()
-
-	body, _ := io.ReadAll(resp.Body)
-
-	// according to https://prometheus.io/docs/concepts/remote_write_spec/
-	// Prometheus remote Write compatible receivers MUST
-	switch resp.StatusCode / 100 {
-	case 2:
-		// respond with a HTTP 2xx status code when the write is successful.
-		return nil
-	case 4:
-		if resp.StatusCode != http.StatusTooManyRequests {
-			// MUST NOT retry write requests on HTTP 4xx responses other than 429
-			return &nonRetriableError{fmt.Errorf("unexpected response code %d for %s. Response body %q",
-				resp.StatusCode, req.URL.Redacted(), body)}
-		}
-		fallthrough
-	default:
-		return fmt.Errorf("unexpected response code %d for %s. Response body %q",
-			resp.StatusCode, req.URL.Redacted(), body)
-	}
-}
-
-type nonRetriableError struct {
-	err error
-}
-
-func (e *nonRetriableError) Error() string {
-	return e.err.Error()
+// RWClient represents an HTTP client for pushing data via remote write protocol
+type RWClient interface {
+	// Push pushes the give time series to remote storage
+	Push(s prompbmarshal.TimeSeries) error
+	// Close stops the client. Client can't be reused after Close call.
+	Close() error
 }
diff --git a/app/vmalert/replay.go b/app/vmalert/replay.go
index 5c9ed96fe..1e4654c7d 100644
--- a/app/vmalert/replay.go
+++ b/app/vmalert/replay.go
@@ -1,19 +1,16 @@
 package main
 
 import (
-	"context"
 	"flag"
 	"fmt"
 	"strings"
 	"time"
 
-	"github.com/cheggaaa/pb/v3"
-
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 )
 
 var (
@@ -33,7 +30,7 @@ var (
 		"Progress bar rendering might be verbose or break the logs parsing, so it is recommended to be disabled when not used in interactive mode.")
 )
 
-func replay(groupsCfg []config.Group, qb datasource.QuerierBuilder, rw *remotewrite.Client) error {
+func replay(groupsCfg []config.Group, qb datasource.QuerierBuilder, rw remotewrite.RWClient) error {
 	if *replayMaxDatapoints < 1 {
 		return fmt.Errorf("replay.maxDatapointsPerQuery can't be lower than 1")
 	}
@@ -68,8 +65,8 @@ func replay(groupsCfg []config.Group, qb datasource.QuerierBuilder, rw *remotewr
 
 	var total int
 	for _, cfg := range groupsCfg {
-		ng := newGroup(cfg, qb, *evaluationInterval, labels)
-		total += ng.replay(tFrom, tTo, rw)
+		ng := rule.NewGroup(cfg, qb, *evaluationInterval, labels)
+		total += ng.Replay(tFrom, tTo, rw, *replayMaxDatapoints, *replayRuleRetryAttempts, *replayRulesDelay, *disableProgressBar)
 	}
 	logger.Infof("replay finished! Imported %d samples", total)
 	if rw != nil {
@@ -77,99 +74,3 @@ func replay(groupsCfg []config.Group, qb datasource.QuerierBuilder, rw *remotewr
 	}
 	return nil
 }
-
-func (g *Group) replay(start, end time.Time, rw *remotewrite.Client) int {
-	var total int
-	step := g.Interval * time.Duration(*replayMaxDatapoints)
-	start = g.adjustReqTimestamp(start)
-	ri := rangeIterator{start: start, end: end, step: step}
-	iterations := int(end.Sub(start)/step) + 1
-	fmt.Printf("\nGroup %q"+
-		"\ninterval: \t%v"+
-		"\neval_offset: \t%v"+
-		"\nrequests to make: \t%d"+
-		"\nmax range per request: \t%v\n",
-		g.Name, g.Interval, g.EvalOffset, iterations, step)
-	if g.Limit > 0 {
-		fmt.Printf("\nPlease note, `limit: %d` param has no effect during replay.\n",
-			g.Limit)
-	}
-	for _, rule := range g.Rules {
-		fmt.Printf("> Rule %q (ID: %d)\n", rule, rule.ID())
-		var bar *pb.ProgressBar
-		if !*disableProgressBar {
-			bar = pb.StartNew(iterations)
-		}
-		ri.reset()
-		for ri.next() {
-			n, err := replayRule(rule, ri.s, ri.e, rw)
-			if err != nil {
-				logger.Fatalf("rule %q: %s", rule, err)
-			}
-			total += n
-			if bar != nil {
-				bar.Increment()
-			}
-		}
-		if bar != nil {
-			bar.Finish()
-		}
-		// sleep to let remote storage to flush data on-disk
-		// so chained rules could be calculated correctly
-		time.Sleep(*replayRulesDelay)
-	}
-	return total
-}
-
-func replayRule(rule Rule, start, end time.Time, rw *remotewrite.Client) (int, error) {
-	var err error
-	var tss []prompbmarshal.TimeSeries
-	for i := 0; i < *replayRuleRetryAttempts; i++ {
-		tss, err = rule.ExecRange(context.Background(), start, end)
-		if err == nil {
-			break
-		}
-		logger.Errorf("attempt %d to execute rule %q failed: %s", i+1, rule, err)
-		time.Sleep(time.Second)
-	}
-	if err != nil { // means all attempts failed
-		return 0, err
-	}
-	if len(tss) < 1 {
-		return 0, nil
-	}
-	var n int
-	for _, ts := range tss {
-		if err := rw.Push(ts); err != nil {
-			return n, fmt.Errorf("remote write failure: %s", err)
-		}
-		n += len(ts.Samples)
-	}
-	return n, nil
-}
-
-type rangeIterator struct {
-	step       time.Duration
-	start, end time.Time
-
-	iter int
-	s, e time.Time
-}
-
-func (ri *rangeIterator) reset() {
-	ri.iter = 0
-	ri.s, ri.e = time.Time{}, time.Time{}
-}
-
-func (ri *rangeIterator) next() bool {
-	ri.s = ri.start.Add(ri.step * time.Duration(ri.iter))
-	if !ri.end.After(ri.s) {
-		return false
-	}
-	ri.e = ri.s.Add(ri.step)
-	if ri.e.After(ri.end) {
-		ri.e = ri.end
-	}
-	ri.iter++
-	return true
-}
diff --git a/app/vmalert/replay_test.go b/app/vmalert/replay_test.go
index bce1856a8..4379c05c1 100644
--- a/app/vmalert/replay_test.go
+++ b/app/vmalert/replay_test.go
@@ -12,7 +12,7 @@ import (
 )
 
 type fakeReplayQuerier struct {
-	fakeQuerier
+	datasource.FakeQuerier
 	registry map[string]map[string]struct{}
 }
 
@@ -170,81 +170,3 @@ func TestReplay(t *testing.T) {
 		})
 	}
 }
-
-func TestRangeIterator(t *testing.T) {
-	testCases := []struct {
-		ri     rangeIterator
-		result [][2]time.Time
-	}{
-		{
-			ri: rangeIterator{
-				start: parseTime(t, "2021-01-01T12:00:00.000Z"),
-				end:   parseTime(t, "2021-01-01T12:30:00.000Z"),
-				step:  5 * time.Minute,
-			},
-			result: [][2]time.Time{
-				{parseTime(t, "2021-01-01T12:00:00.000Z"), parseTime(t, "2021-01-01T12:05:00.000Z")},
-				{parseTime(t, "2021-01-01T12:05:00.000Z"), parseTime(t, "2021-01-01T12:10:00.000Z")},
-				{parseTime(t, "2021-01-01T12:10:00.000Z"), parseTime(t, "2021-01-01T12:15:00.000Z")},
-				{parseTime(t, "2021-01-01T12:15:00.000Z"), parseTime(t, "2021-01-01T12:20:00.000Z")},
-				{parseTime(t, "2021-01-01T12:20:00.000Z"), parseTime(t, "2021-01-01T12:25:00.000Z")},
-				{parseTime(t, "2021-01-01T12:25:00.000Z"), parseTime(t, "2021-01-01T12:30:00.000Z")},
-			},
-		},
-		{
-			ri: rangeIterator{
-				start: parseTime(t, "2021-01-01T12:00:00.000Z"),
-				end:   parseTime(t, "2021-01-01T12:30:00.000Z"),
-				step:  45 * time.Minute,
-			},
-			result: [][2]time.Time{
-				{parseTime(t, "2021-01-01T12:00:00.000Z"), parseTime(t, "2021-01-01T12:30:00.000Z")},
-				{parseTime(t, "2021-01-01T12:30:00.000Z"), parseTime(t, "2021-01-01T12:30:00.000Z")},
-			},
-		},
-		{
-			ri: rangeIterator{
-				start: parseTime(t, "2021-01-01T12:00:12.000Z"),
-				end:   parseTime(t, "2021-01-01T12:00:17.000Z"),
-				step:  time.Second,
-			},
-			result: [][2]time.Time{
-				{parseTime(t, "2021-01-01T12:00:12.000Z"), parseTime(t, "2021-01-01T12:00:13.000Z")},
-				{parseTime(t, "2021-01-01T12:00:13.000Z"), parseTime(t, "2021-01-01T12:00:14.000Z")},
-				{parseTime(t, "2021-01-01T12:00:14.000Z"), parseTime(t, "2021-01-01T12:00:15.000Z")},
-				{parseTime(t, "2021-01-01T12:00:15.000Z"), parseTime(t, "2021-01-01T12:00:16.000Z")},
-				{parseTime(t, "2021-01-01T12:00:16.000Z"), parseTime(t, "2021-01-01T12:00:17.000Z")},
-			},
-		},
-	}
-
-	for i, tc := range testCases {
-		t.Run(fmt.Sprintf("case %d", i), func(t *testing.T) {
-			var j int
-			for tc.ri.next() {
-				if len(tc.result) < j+1 {
-					t.Fatalf("unexpected result for iterator on step %d: %v - %v",
-						j, tc.ri.s, tc.ri.e)
-				}
-				s, e := tc.ri.s, tc.ri.e
-				expS, expE := tc.result[j][0], tc.result[j][1]
-				if s != expS {
-					t.Fatalf("expected to get start=%v; got %v", expS, s)
-				}
-				if e != expE {
-					t.Fatalf("expected to get end=%v; got %v", expE, e)
-				}
-				j++
-			}
-		})
-	}
-}
-
-func parseTime(t *testing.T, s string) time.Time {
-	t.Helper()
-	tt, err := time.Parse("2006-01-02T15:04:05.000Z", s)
-	if err != nil {
-		t.Fatal(err)
-	}
-	return tt
-}
diff --git a/app/vmalert/rule.go b/app/vmalert/rule.go
deleted file mode 100644
index e2860f9c8..000000000
--- a/app/vmalert/rule.go
+++ /dev/null
@@ -1,118 +0,0 @@
-package main
-
-import (
-	"context"
-	"errors"
-	"sync"
-	"time"
-
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
-)
-
-// Rule represents alerting or recording rule
-// that has unique ID, can be Executed and
-// updated with other Rule.
-type Rule interface {
-	// ID returns unique ID that may be used for
-	// identifying this Rule among others.
-	ID() uint64
-	// Exec executes the rule with given context at the given timestamp and limit.
-	// returns an err if number of resulting time series exceeds the limit.
-	Exec(ctx context.Context, ts time.Time, limit int) ([]prompbmarshal.TimeSeries, error)
-	// ExecRange executes the rule on the given time range.
-	ExecRange(ctx context.Context, start, end time.Time) ([]prompbmarshal.TimeSeries, error)
-	// UpdateWith performs modification of current Rule
-	// with fields of the given Rule.
-	UpdateWith(Rule) error
-	// ToAPI converts Rule into APIRule
-	ToAPI() APIRule
-	// Close performs the shutdown procedures for rule
-	// such as metrics unregister
-	Close()
-}
-
-var errDuplicate = errors.New("result contains metrics with the same labelset after applying rule labels. See https://docs.victoriametrics.com/vmalert.html#series-with-the-same-labelset for details")
-
-type ruleState struct {
-	sync.RWMutex
-	entries []ruleStateEntry
-	cur     int
-}
-
-type ruleStateEntry struct {
-	// stores last moment of time rule.Exec was called
-	time time.Time
-	// stores the timestamp rule.Exec was called with
-	at time.Time
-	// stores the duration of the last rule.Exec call
-	duration time.Duration
-	// stores last error that happened in Exec func
-	// resets on every successful Exec
-	// may be used as Health ruleState
-	err error
-	// stores the number of samples returned during
-	// the last evaluation
-	samples int
-	// stores the number of time series fetched during
-	// the last evaluation.
-	// Is supported by VictoriaMetrics only, starting from v1.90.0
-	// If seriesFetched == nil, then this attribute was missing in
-	// datasource response (unsupported).
-	seriesFetched *int
-	// stores the curl command reflecting the HTTP request used during rule.Exec
-	curl string
-}
-
-func newRuleState(size int) *ruleState {
-	if size < 1 {
-		size = 1
-	}
-	return &ruleState{
-		entries: make([]ruleStateEntry, size),
-	}
-}
-
-func (s *ruleState) getLast() ruleStateEntry {
-	s.RLock()
-	defer s.RUnlock()
-	return s.entries[s.cur]
-}
-
-func (s *ruleState) size() int {
-	s.RLock()
-	defer s.RUnlock()
-	return len(s.entries)
-}
-
-func (s *ruleState) getAll() []ruleStateEntry {
-	entries := make([]ruleStateEntry, 0)
-
-	s.RLock()
-	defer s.RUnlock()
-
-	cur := s.cur
-	for {
-		e := s.entries[cur]
-		if !e.time.IsZero() || !e.at.IsZero() {
-			entries = append(entries, e)
-		}
-		cur--
-		if cur < 0 {
-			cur = cap(s.entries) - 1
-		}
-		if cur == s.cur {
-			return entries
-		}
-	}
-}
-
-func (s *ruleState) add(e ruleStateEntry) {
-	s.Lock()
-	defer s.Unlock()
-
-	s.cur++
-	if s.cur > cap(s.entries)-1 {
-		s.cur = 0
-	}
-	s.entries[s.cur] = e
-}
diff --git a/app/vmalert/alerting.go b/app/vmalert/rule/alerting.go
similarity index 81%
rename from app/vmalert/alerting.go
rename to app/vmalert/rule/alerting.go
index 779423b6f..a1a6e34dc 100644
--- a/app/vmalert/alerting.go
+++ b/app/vmalert/rule/alerting.go
@@ -1,11 +1,10 @@
-package main
+package rule
 
 import (
 	"context"
 	"fmt"
 	"hash/fnv"
 	"sort"
-	"strconv"
 	"strings"
 	"sync"
 	"time"
@@ -55,7 +54,8 @@ type alertingRuleMetrics struct {
 	seriesFetched *utils.Gauge
 }
 
-func newAlertingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rule) *AlertingRule {
+// NewAlertingRule creates a new AlertingRule
+func NewAlertingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rule) *AlertingRule {
 	ar := &AlertingRule{
 		Type:          group.Type,
 		RuleID:        cfg.ID,
@@ -80,10 +80,15 @@ func newAlertingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rule
 		metrics: &alertingRuleMetrics{},
 	}
 
+	entrySize := *ruleUpdateEntriesLimit
 	if cfg.UpdateEntriesLimit != nil {
-		ar.state = newRuleState(*cfg.UpdateEntriesLimit)
-	} else {
-		ar.state = newRuleState(*ruleUpdateEntriesLimit)
+		entrySize = *cfg.UpdateEntriesLimit
+	}
+	if entrySize < 1 {
+		entrySize = 1
+	}
+	ar.state = &ruleState{
+		entries: make([]StateEntry, entrySize),
 	}
 
 	labels := fmt.Sprintf(`alertname=%q, group=%q, id="%d"`, ar.Name, group.Name, ar.ID())
@@ -114,7 +119,7 @@ func newAlertingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rule
 	ar.metrics.errors = utils.GetOrCreateGauge(fmt.Sprintf(`vmalert_alerting_rules_error{%s}`, labels),
 		func() float64 {
 			e := ar.state.getLast()
-			if e.err == nil {
+			if e.Err == nil {
 				return 0
 			}
 			return 1
@@ -122,28 +127,28 @@ func newAlertingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rule
 	ar.metrics.samples = utils.GetOrCreateGauge(fmt.Sprintf(`vmalert_alerting_rules_last_evaluation_samples{%s}`, labels),
 		func() float64 {
 			e := ar.state.getLast()
-			return float64(e.samples)
+			return float64(e.Samples)
 		})
 	ar.metrics.seriesFetched = utils.GetOrCreateGauge(fmt.Sprintf(`vmalert_alerting_rules_last_evaluation_series_fetched{%s}`, labels),
 		func() float64 {
 			e := ar.state.getLast()
-			if e.seriesFetched == nil {
+			if e.SeriesFetched == nil {
 				// means seriesFetched is unsupported
 				return -1
 			}
-			seriesFetched := float64(*e.seriesFetched)
-			if seriesFetched == 0 && e.samples > 0 {
+			seriesFetched := float64(*e.SeriesFetched)
+			if seriesFetched == 0 && e.Samples > 0 {
 				// `alert: 0.95` will fetch no series
 				// but will get one time series in response.
-				seriesFetched = float64(e.samples)
+				seriesFetched = float64(e.Samples)
 			}
 			return seriesFetched
 		})
 	return ar
 }
 
-// Close unregisters rule metrics
-func (ar *AlertingRule) Close() {
+// close unregisters rule metrics
+func (ar *AlertingRule) close() {
 	ar.metrics.active.Unregister()
 	ar.metrics.pending.Unregister()
 	ar.metrics.errors.Unregister()
@@ -162,6 +167,27 @@ func (ar *AlertingRule) ID() uint64 {
 	return ar.RuleID
 }
 
+// GetAlerts returns active alerts of rule
+func (ar *AlertingRule) GetAlerts() []*notifier.Alert {
+	ar.alertsMu.RLock()
+	defer ar.alertsMu.RUnlock()
+	var alerts []*notifier.Alert
+	for _, a := range ar.alerts {
+		alerts = append(alerts, a)
+	}
+	return alerts
+}
+
+// GetAlert returns alert if id exists
+func (ar *AlertingRule) GetAlert(id uint64) *notifier.Alert {
+	ar.alertsMu.RLock()
+	defer ar.alertsMu.RUnlock()
+	if ar.alerts == nil {
+		return nil
+	}
+	return ar.alerts[id]
+}
+
 func (ar *AlertingRule) logDebugf(at time.Time, a *notifier.Alert, format string, args ...interface{}) {
 	if !ar.Debug {
 		return
@@ -188,6 +214,26 @@ func (ar *AlertingRule) logDebugf(at time.Time, a *notifier.Alert, format string
 	logger.Infof("%s", prefix+msg)
 }
 
+// updateWith copies all significant fields.
+// alerts state isn't copied since
+// it should be updated in next 2 Execs
+func (ar *AlertingRule) updateWith(r Rule) error {
+	nr, ok := r.(*AlertingRule)
+	if !ok {
+		return fmt.Errorf("BUG: attempt to update alerting rule with wrong type %#v", r)
+	}
+	ar.Expr = nr.Expr
+	ar.For = nr.For
+	ar.KeepFiringFor = nr.KeepFiringFor
+	ar.Labels = nr.Labels
+	ar.Annotations = nr.Annotations
+	ar.EvalInterval = nr.EvalInterval
+	ar.Debug = nr.Debug
+	ar.q = nr.q
+	ar.state = nr.state
+	return nil
+}
+
 type labelSet struct {
 	// origin labels extracted from received time series
 	// plus extra labels (group labels, service labels like alertNameLabel).
@@ -248,11 +294,11 @@ func (ar *AlertingRule) toLabels(m datasource.Metric, qFn templates.QueryFn) (*l
 	return ls, nil
 }
 
-// ExecRange executes alerting rule on the given time range similarly to Exec.
+// execRange executes alerting rule on the given time range similarly to exec.
 // It doesn't update internal states of the Rule and meant to be used just
 // to get time series for backfilling.
 // It returns ALERT and ALERT_FOR_STATE time series as result.
-func (ar *AlertingRule) ExecRange(ctx context.Context, start, end time.Time) ([]prompbmarshal.TimeSeries, error) {
+func (ar *AlertingRule) execRange(ctx context.Context, start, end time.Time) ([]prompbmarshal.TimeSeries, error) {
 	res, err := ar.q.QueryRange(ctx, ar.Expr, start, end)
 	if err != nil {
 		return nil, err
@@ -297,19 +343,19 @@ func (ar *AlertingRule) ExecRange(ctx context.Context, start, end time.Time) ([]
 // is kept in memory state and consequently repeatedly sent to the AlertManager.
 const resolvedRetention = 15 * time.Minute
 
-// Exec executes AlertingRule expression via the given Querier.
+// exec executes AlertingRule expression via the given Querier.
 // Based on the Querier results AlertingRule maintains notifier.Alerts
-func (ar *AlertingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]prompbmarshal.TimeSeries, error) {
+func (ar *AlertingRule) exec(ctx context.Context, ts time.Time, limit int) ([]prompbmarshal.TimeSeries, error) {
 	start := time.Now()
 	res, req, err := ar.q.Query(ctx, ar.Expr, ts)
-	curState := ruleStateEntry{
-		time:          start,
-		at:            ts,
-		duration:      time.Since(start),
-		samples:       len(res.Data),
-		seriesFetched: res.SeriesFetched,
-		err:           err,
-		curl:          requestToCurl(req),
+	curState := StateEntry{
+		Time:          start,
+		At:            ts,
+		Duration:      time.Since(start),
+		Samples:       len(res.Data),
+		SeriesFetched: res.SeriesFetched,
+		Err:           err,
+		Curl:          requestToCurl(req),
 	}
 
 	defer func() {
@@ -323,7 +369,7 @@ func (ar *AlertingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]pr
 		return nil, fmt.Errorf("failed to execute query %q: %w", ar.Expr, err)
 	}
 
-	ar.logDebugf(ts, nil, "query returned %d samples (elapsed: %s)", curState.samples, curState.duration)
+	ar.logDebugf(ts, nil, "query returned %d samples (elapsed: %s)", curState.Samples, curState.Duration)
 
 	for h, a := range ar.alerts {
 		// cleanup inactive alerts from previous Exec
@@ -342,15 +388,15 @@ func (ar *AlertingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]pr
 	for _, m := range res.Data {
 		ls, err := ar.toLabels(m, qFn)
 		if err != nil {
-			curState.err = fmt.Errorf("failed to expand labels: %s", err)
-			return nil, curState.err
+			curState.Err = fmt.Errorf("failed to expand labels: %s", err)
+			return nil, curState.Err
 		}
 		h := hash(ls.processed)
 		if _, ok := updated[h]; ok {
 			// duplicate may be caused by extra labels
 			// conflicting with the metric labels
-			curState.err = fmt.Errorf("labels %v: %w", ls.processed, errDuplicate)
-			return nil, curState.err
+			curState.Err = fmt.Errorf("labels %v: %w", ls.processed, errDuplicate)
+			return nil, curState.Err
 		}
 		updated[h] = struct{}{}
 		if a, ok := ar.alerts[h]; ok {
@@ -373,8 +419,8 @@ func (ar *AlertingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]pr
 		}
 		a, err := ar.newAlert(m, ls, start, qFn)
 		if err != nil {
-			curState.err = fmt.Errorf("failed to create alert: %w", err)
-			return nil, curState.err
+			curState.Err = fmt.Errorf("failed to create alert: %w", err)
+			return nil, curState.Err
 		}
 		a.ID = h
 		a.State = notifier.StatePending
@@ -423,8 +469,8 @@ func (ar *AlertingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]pr
 	}
 	if limit > 0 && numActivePending > limit {
 		ar.alerts = map[uint64]*notifier.Alert{}
-		curState.err = fmt.Errorf("exec exceeded limit of %d with %d alerts", limit, numActivePending)
-		return nil, curState.err
+		curState.Err = fmt.Errorf("exec exceeded limit of %d with %d alerts", limit, numActivePending)
+		return nil, curState.Err
 	}
 	return ar.toTimeSeries(ts.Unix()), nil
 }
@@ -441,26 +487,6 @@ func (ar *AlertingRule) toTimeSeries(timestamp int64) []prompbmarshal.TimeSeries
 	return tss
 }
 
-// UpdateWith copies all significant fields.
-// alerts state isn't copied since
-// it should be updated in next 2 Execs
-func (ar *AlertingRule) UpdateWith(r Rule) error {
-	nr, ok := r.(*AlertingRule)
-	if !ok {
-		return fmt.Errorf("BUG: attempt to update alerting rule with wrong type %#v", r)
-	}
-	ar.Expr = nr.Expr
-	ar.For = nr.For
-	ar.KeepFiringFor = nr.KeepFiringFor
-	ar.Labels = nr.Labels
-	ar.Annotations = nr.Annotations
-	ar.EvalInterval = nr.EvalInterval
-	ar.Debug = nr.Debug
-	ar.q = nr.q
-	ar.state = nr.state
-	return nil
-}
-
 // TODO: consider hashing algorithm in VM
 func hash(labels map[string]string) uint64 {
 	hash := fnv.New64a()
@@ -503,102 +529,6 @@ func (ar *AlertingRule) newAlert(m datasource.Metric, ls *labelSet, start time.T
 	return a, err
 }
 
-// AlertAPI generates APIAlert object from alert by its id(hash)
-func (ar *AlertingRule) AlertAPI(id uint64) *APIAlert {
-	ar.alertsMu.RLock()
-	defer ar.alertsMu.RUnlock()
-	a, ok := ar.alerts[id]
-	if !ok {
-		return nil
-	}
-	return ar.newAlertAPI(*a)
-}
-
-// ToAPI returns Rule representation in form of APIRule
-// Isn't thread-safe. Call must be protected by AlertingRule mutex.
-func (ar *AlertingRule) ToAPI() APIRule {
-	lastState := ar.state.getLast()
-	r := APIRule{
-		Type:              "alerting",
-		DatasourceType:    ar.Type.String(),
-		Name:              ar.Name,
-		Query:             ar.Expr,
-		Duration:          ar.For.Seconds(),
-		KeepFiringFor:     ar.KeepFiringFor.Seconds(),
-		Labels:            ar.Labels,
-		Annotations:       ar.Annotations,
-		LastEvaluation:    lastState.time,
-		EvaluationTime:    lastState.duration.Seconds(),
-		Health:            "ok",
-		State:             "inactive",
-		Alerts:            ar.AlertsToAPI(),
-		LastSamples:       lastState.samples,
-		LastSeriesFetched: lastState.seriesFetched,
-		MaxUpdates:        ar.state.size(),
-		Updates:           ar.state.getAll(),
-		Debug:             ar.Debug,
-
-		// encode as strings to avoid rounding in JSON
-		ID:      fmt.Sprintf("%d", ar.ID()),
-		GroupID: fmt.Sprintf("%d", ar.GroupID),
-	}
-	if lastState.err != nil {
-		r.LastError = lastState.err.Error()
-		r.Health = "err"
-	}
-	// satisfy APIRule.State logic
-	if len(r.Alerts) > 0 {
-		r.State = notifier.StatePending.String()
-		stateFiring := notifier.StateFiring.String()
-		for _, a := range r.Alerts {
-			if a.State == stateFiring {
-				r.State = stateFiring
-				break
-			}
-		}
-	}
-	return r
-}
-
-// AlertsToAPI generates list of APIAlert objects from existing alerts
-func (ar *AlertingRule) AlertsToAPI() []*APIAlert {
-	var alerts []*APIAlert
-	ar.alertsMu.RLock()
-	for _, a := range ar.alerts {
-		if a.State == notifier.StateInactive {
-			continue
-		}
-		alerts = append(alerts, ar.newAlertAPI(*a))
-	}
-	ar.alertsMu.RUnlock()
-	return alerts
-}
-
-func (ar *AlertingRule) newAlertAPI(a notifier.Alert) *APIAlert {
-	aa := &APIAlert{
-		// encode as strings to avoid rounding
-		ID:      fmt.Sprintf("%d", a.ID),
-		GroupID: fmt.Sprintf("%d", a.GroupID),
-		RuleID:  fmt.Sprintf("%d", ar.RuleID),
-
-		Name:        a.Name,
-		Expression:  ar.Expr,
-		Labels:      a.Labels,
-		Annotations: a.Annotations,
-		State:       a.State.String(),
-		ActiveAt:    a.ActiveAt,
-		Restored:    a.Restored,
-		Value:       strconv.FormatFloat(a.Value, 'f', -1, 32),
-	}
-	if alertURLGeneratorFn != nil {
-		aa.SourceLink = alertURLGeneratorFn(a)
-	}
-	if a.State == notifier.StateFiring && !a.KeepFiringSince.IsZero() {
-		aa.Stabilizing = true
-	}
-	return aa
-}
-
 const (
 	// alertMetricName is the metric name for synthetic alert timeseries.
 	alertMetricName = "ALERTS"
@@ -646,10 +576,10 @@ func alertForToTimeSeries(a *notifier.Alert, timestamp int64) prompbmarshal.Time
 	return newTimeSeries([]float64{float64(a.ActiveAt.Unix())}, []int64{timestamp}, labels)
 }
 
-// Restore restores the value of ActiveAt field for active alerts,
+// restore restores the value of ActiveAt field for active alerts,
 // based on previously written time series `alertForStateMetricName`.
 // Only rules with For > 0 can be restored.
-func (ar *AlertingRule) Restore(ctx context.Context, q datasource.Querier, ts time.Time, lookback time.Duration) error {
+func (ar *AlertingRule) restore(ctx context.Context, q datasource.Querier, ts time.Time, lookback time.Duration) error {
 	if ar.For < 1 {
 		return nil
 	}
diff --git a/app/vmalert/alerting_test.go b/app/vmalert/rule/alerting_test.go
similarity index 94%
rename from app/vmalert/alerting_test.go
rename to app/vmalert/rule/alerting_test.go
index 9fdcb5861..cfb8fdbf3 100644
--- a/app/vmalert/alerting_test.go
+++ b/app/vmalert/rule/alerting_test.go
@@ -1,4 +1,4 @@
-package main
+package rule
 
 import (
 	"context"
@@ -303,13 +303,13 @@ func TestAlertingRule_Exec(t *testing.T) {
 	fakeGroup := Group{Name: "TestRule_Exec"}
 	for _, tc := range testCases {
 		t.Run(tc.rule.Name, func(t *testing.T) {
-			fq := &fakeQuerier{}
+			fq := &datasource.FakeQuerier{}
 			tc.rule.q = fq
 			tc.rule.GroupID = fakeGroup.ID()
 			for i, step := range tc.steps {
-				fq.reset()
-				fq.add(step...)
-				if _, err := tc.rule.Exec(context.TODO(), time.Now(), 0); err != nil {
+				fq.Reset()
+				fq.Add(step...)
+				if _, err := tc.rule.exec(context.TODO(), time.Now(), 0); err != nil {
 					t.Fatalf("unexpected err: %s", err)
 				}
 				// artificial delay between applying steps
@@ -482,11 +482,11 @@ func TestAlertingRule_ExecRange(t *testing.T) {
 	fakeGroup := Group{Name: "TestRule_ExecRange"}
 	for _, tc := range testCases {
 		t.Run(tc.rule.Name, func(t *testing.T) {
-			fq := &fakeQuerier{}
+			fq := &datasource.FakeQuerier{}
 			tc.rule.q = fq
 			tc.rule.GroupID = fakeGroup.ID()
-			fq.add(tc.data...)
-			gotTS, err := tc.rule.ExecRange(context.TODO(), time.Now(), time.Now())
+			fq.Add(tc.data...)
+			gotTS, err := tc.rule.execRange(context.TODO(), time.Now(), time.Now())
 			if err != nil {
 				t.Fatalf("unexpected err: %s", err)
 			}
@@ -518,24 +518,24 @@ func TestAlertingRule_ExecRange(t *testing.T) {
 
 func TestGroup_Restore(t *testing.T) {
 	defaultTS := time.Now()
-	fqr := &fakeQuerierWithRegistry{}
+	fqr := &datasource.FakeQuerierWithRegistry{}
 	fn := func(rules []config.Rule, expAlerts map[uint64]*notifier.Alert) {
 		t.Helper()
-		defer fqr.reset()
+		defer fqr.Reset()
 
 		for _, r := range rules {
-			fqr.set(r.Expr, metricWithValueAndLabels(t, 0, "__name__", r.Alert))
+			fqr.Set(r.Expr, metricWithValueAndLabels(t, 0, "__name__", r.Alert))
 		}
 
-		fg := newGroup(config.Group{Name: "TestRestore", Rules: rules}, fqr, time.Second, nil)
+		fg := NewGroup(config.Group{Name: "TestRestore", Rules: rules}, fqr, time.Second, nil)
 		wg := sync.WaitGroup{}
 		wg.Add(1)
 		go func() {
-			nts := func() []notifier.Notifier { return []notifier.Notifier{&fakeNotifier{}} }
-			fg.start(context.Background(), nts, nil, fqr)
+			nts := func() []notifier.Notifier { return []notifier.Notifier{&notifier.FakeNotifier{}} }
+			fg.Start(context.Background(), nts, nil, fqr)
 			wg.Done()
 		}()
-		fg.close()
+		fg.Close()
 		wg.Wait()
 
 		gotAlerts := make(map[uint64]*notifier.Alert)
@@ -582,11 +582,11 @@ func TestGroup_Restore(t *testing.T) {
 				ActiveAt: defaultTS,
 			},
 		})
-	fqr.reset()
+	fqr.Reset()
 
 	// one active alert with state restore
 	ts := time.Now().Truncate(time.Hour)
-	fqr.set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="foo"}[3600s])`,
+	fqr.Set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="foo"}[3600s])`,
 		stateMetric("foo", ts))
 	fn(
 		[]config.Rule{{Alert: "foo", Expr: "foo", For: promutils.NewDuration(time.Second)}},
@@ -598,7 +598,7 @@ func TestGroup_Restore(t *testing.T) {
 
 	// two rules, two active alerts, one with state restored
 	ts = time.Now().Truncate(time.Hour)
-	fqr.set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="bar"}[3600s])`,
+	fqr.Set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="bar"}[3600s])`,
 		stateMetric("foo", ts))
 	fn(
 		[]config.Rule{
@@ -616,9 +616,9 @@ func TestGroup_Restore(t *testing.T) {
 
 	// two rules, two active alerts, two with state restored
 	ts = time.Now().Truncate(time.Hour)
-	fqr.set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="foo"}[3600s])`,
+	fqr.Set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="foo"}[3600s])`,
 		stateMetric("foo", ts))
-	fqr.set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="bar"}[3600s])`,
+	fqr.Set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="bar"}[3600s])`,
 		stateMetric("bar", ts))
 	fn(
 		[]config.Rule{
@@ -636,7 +636,7 @@ func TestGroup_Restore(t *testing.T) {
 
 	// one active alert but wrong state restore
 	ts = time.Now().Truncate(time.Hour)
-	fqr.set(`last_over_time(ALERTS_FOR_STATE{alertname="bar",alertgroup="TestRestore"}[3600s])`,
+	fqr.Set(`last_over_time(ALERTS_FOR_STATE{alertname="bar",alertgroup="TestRestore"}[3600s])`,
 		stateMetric("wrong alert", ts))
 	fn(
 		[]config.Rule{{Alert: "foo", Expr: "foo", For: promutils.NewDuration(time.Second)}},
@@ -648,7 +648,7 @@ func TestGroup_Restore(t *testing.T) {
 
 	// one active alert with labels
 	ts = time.Now().Truncate(time.Hour)
-	fqr.set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="foo",env="dev"}[3600s])`,
+	fqr.Set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="foo",env="dev"}[3600s])`,
 		stateMetric("foo", ts, "env", "dev"))
 	fn(
 		[]config.Rule{{Alert: "foo", Expr: "foo", Labels: map[string]string{"env": "dev"}, For: promutils.NewDuration(time.Second)}},
@@ -660,7 +660,7 @@ func TestGroup_Restore(t *testing.T) {
 
 	// one active alert with restore labels missmatch
 	ts = time.Now().Truncate(time.Hour)
-	fqr.set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="foo",env="dev"}[3600s])`,
+	fqr.Set(`last_over_time(ALERTS_FOR_STATE{alertgroup="TestRestore",alertname="foo",env="dev"}[3600s])`,
 		stateMetric("foo", ts, "env", "dev", "team", "foo"))
 	fn(
 		[]config.Rule{{Alert: "foo", Expr: "foo", Labels: map[string]string{"env": "dev"}, For: promutils.NewDuration(time.Second)}},
@@ -672,30 +672,30 @@ func TestGroup_Restore(t *testing.T) {
 }
 
 func TestAlertingRule_Exec_Negative(t *testing.T) {
-	fq := &fakeQuerier{}
+	fq := &datasource.FakeQuerier{}
 	ar := newTestAlertingRule("test", 0)
 	ar.Labels = map[string]string{"job": "test"}
 	ar.q = fq
 
 	// successful attempt
-	fq.add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "bar"))
-	_, err := ar.Exec(context.TODO(), time.Now(), 0)
+	fq.Add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "bar"))
+	_, err := ar.exec(context.TODO(), time.Now(), 0)
 	if err != nil {
 		t.Fatal(err)
 	}
 
 	// label `job` will collide with rule extra label and will make both time series equal
-	fq.add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "baz"))
-	_, err = ar.Exec(context.TODO(), time.Now(), 0)
+	fq.Add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "baz"))
+	_, err = ar.exec(context.TODO(), time.Now(), 0)
 	if !errors.Is(err, errDuplicate) {
 		t.Fatalf("expected to have %s error; got %s", errDuplicate, err)
 	}
 
-	fq.reset()
+	fq.Reset()
 
 	expErr := "connection reset by peer"
-	fq.setErr(errors.New(expErr))
-	_, err = ar.Exec(context.TODO(), time.Now(), 0)
+	fq.SetErr(errors.New(expErr))
+	_, err = ar.exec(context.TODO(), time.Now(), 0)
 	if err == nil {
 		t.Fatalf("expected to get err; got nil")
 	}
@@ -705,7 +705,7 @@ func TestAlertingRule_Exec_Negative(t *testing.T) {
 }
 
 func TestAlertingRuleLimit(t *testing.T) {
-	fq := &fakeQuerier{}
+	fq := &datasource.FakeQuerier{}
 	ar := newTestAlertingRule("test", 0)
 	ar.Labels = map[string]string{"job": "test"}
 	ar.q = fq
@@ -737,15 +737,15 @@ func TestAlertingRuleLimit(t *testing.T) {
 		err       error
 		timestamp = time.Now()
 	)
-	fq.add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "bar"))
-	fq.add(metricWithValueAndLabels(t, 1, "__name__", "foo", "bar", "job"))
+	fq.Add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "bar"))
+	fq.Add(metricWithValueAndLabels(t, 1, "__name__", "foo", "bar", "job"))
 	for _, testCase := range testCases {
-		_, err = ar.Exec(context.TODO(), timestamp, testCase.limit)
+		_, err = ar.exec(context.TODO(), timestamp, testCase.limit)
 		if err != nil && !strings.EqualFold(err.Error(), testCase.err) {
 			t.Fatal(err)
 		}
 	}
-	fq.reset()
+	fq.Reset()
 }
 
 func TestAlertingRule_Template(t *testing.T) {
@@ -870,12 +870,12 @@ func TestAlertingRule_Template(t *testing.T) {
 	fakeGroup := Group{Name: "TestRule_Exec"}
 	for _, tc := range testCases {
 		t.Run(tc.rule.Name, func(t *testing.T) {
-			fq := &fakeQuerier{}
+			fq := &datasource.FakeQuerier{}
 			tc.rule.GroupID = fakeGroup.ID()
 			tc.rule.q = fq
-			tc.rule.state = newRuleState(10)
-			fq.add(tc.metrics...)
-			if _, err := tc.rule.Exec(context.TODO(), time.Now(), 0); err != nil {
+			tc.rule.state = &ruleState{entries: make([]StateEntry, 10)}
+			fq.Add(tc.metrics...)
+			if _, err := tc.rule.exec(context.TODO(), time.Now(), 0); err != nil {
 				t.Fatalf("unexpected err: %s", err)
 			}
 			for hash, expAlert := range tc.expAlerts {
@@ -989,7 +989,7 @@ func newTestAlertingRule(name string, waitFor time.Duration) *AlertingRule {
 		For:          waitFor,
 		EvalInterval: waitFor,
 		alerts:       make(map[uint64]*notifier.Alert),
-		state:        newRuleState(10),
+		state:        &ruleState{entries: make([]StateEntry, 10)},
 	}
 	return &rule
 }
diff --git a/app/vmalert/group.go b/app/vmalert/rule/group.go
similarity index 73%
rename from app/vmalert/group.go
rename to app/vmalert/rule/group.go
index 8ccd1e7bc..29f350373 100644
--- a/app/vmalert/group.go
+++ b/app/vmalert/rule/group.go
@@ -1,8 +1,10 @@
-package main
+package rule
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
+	"flag"
 	"fmt"
 	"hash/fnv"
 	"net/url"
@@ -11,7 +13,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/VictoriaMetrics/metrics"
+	"github.com/cheggaaa/pb/v3"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
@@ -21,6 +23,18 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/decimal"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
+	"github.com/VictoriaMetrics/metrics"
+)
+
+var (
+	ruleUpdateEntriesLimit = flag.Int("rule.updateEntriesLimit", 20, "Defines the max number of rule's state updates stored in-memory. "+
+		"Rule's updates are available on rule's Details page and are used for debugging purposes. The number of stored updates can be overridden per rule via update_entries_limit param.")
+	resendDelay        = flag.Duration("rule.resendDelay", 0, "MiniMum amount of time to wait before resending an alert to notifier")
+	maxResolveDuration = flag.Duration("rule.maxResolveDuration", 0, "Limits the maxiMum duration for automatic alert expiration, "+
+		"which by default is 4 times evaluationInterval of the parent ")
+	disableAlertGroupLabel = flag.Bool("disableAlertgroupLabel", false, "Whether to disable adding group's Name as label to generated alerts and time series.")
+	remoteReadLookBack     = flag.Duration("remoteRead.lookback", time.Hour, "Lookback defines how far to look into past for alerts timeseries."+
+		" For example, if lookback=1h then range from now() to now()-1h will be scanned.")
 )
 
 // Group is an entity for grouping rules
@@ -96,7 +110,8 @@ func mergeLabels(groupName, ruleName string, set1, set2 map[string]string) map[s
 	return r
 }
 
-func newGroup(cfg config.Group, qb datasource.QuerierBuilder, defaultInterval time.Duration, labels map[string]string) *Group {
+// NewGroup returns a new group
+func NewGroup(cfg config.Group, qb datasource.QuerierBuilder, defaultInterval time.Duration, labels map[string]string) *Group {
 	g := &Group{
 		Type:            cfg.Type,
 		Name:            cfg.Name,
@@ -153,11 +168,11 @@ func newGroup(cfg config.Group, qb datasource.QuerierBuilder, defaultInterval ti
 	return g
 }
 
-func (g *Group) newRule(qb datasource.QuerierBuilder, rule config.Rule) Rule {
-	if rule.Alert != "" {
-		return newAlertingRule(qb, g, rule)
+func (g *Group) newRule(qb datasource.QuerierBuilder, r config.Rule) Rule {
+	if r.Alert != "" {
+		return NewAlertingRule(qb, g, r)
 	}
-	return newRecordingRule(qb, g, rule)
+	return NewRecordingRule(qb, g, r)
 }
 
 // ID return unique group ID that consists of
@@ -178,8 +193,8 @@ func (g *Group) ID() uint64 {
 	return hash.Sum64()
 }
 
-// Restore restores alerts state for group rules
-func (g *Group) Restore(ctx context.Context, qb datasource.QuerierBuilder, ts time.Time, lookback time.Duration) error {
+// restore restores alerts state for group rules
+func (g *Group) restore(ctx context.Context, qb datasource.QuerierBuilder, ts time.Time, lookback time.Duration) error {
 	for _, rule := range g.Rules {
 		ar, ok := rule.(*AlertingRule)
 		if !ok {
@@ -195,7 +210,7 @@ func (g *Group) Restore(ctx context.Context, qb datasource.QuerierBuilder, ts ti
 			Headers:            g.Headers,
 			Debug:              ar.Debug,
 		})
-		if err := ar.Restore(ctx, q, ts, lookback); err != nil {
+		if err := ar.restore(ctx, q, ts, lookback); err != nil {
 			return fmt.Errorf("error while restoring rule %q: %w", rule, err)
 		}
 	}
@@ -205,7 +220,7 @@ func (g *Group) Restore(ctx context.Context, qb datasource.QuerierBuilder, ts ti
 // updateWith updates existing group with
 // passed group object. This function ignores group
 // evaluation interval change. It supposed to be updated
-// in group.start function.
+// in group.Start function.
 // Not thread-safe.
 func (g *Group) updateWith(newGroup *Group) error {
 	rulesRegistry := make(map[uint64]Rule)
@@ -218,11 +233,11 @@ func (g *Group) updateWith(newGroup *Group) error {
 		if !ok {
 			// old rule is not present in the new list
 			// so we mark it for removing
-			g.Rules[i].Close()
+			g.Rules[i].close()
 			g.Rules[i] = nil
 			continue
 		}
-		if err := or.UpdateWith(nr); err != nil {
+		if err := or.updateWith(nr); err != nil {
 			return err
 		}
 		delete(rulesRegistry, nr.ID())
@@ -255,10 +270,10 @@ func (g *Group) updateWith(newGroup *Group) error {
 	return nil
 }
 
-// interruptEval interrupts in-flight rules evaluations
+// InterruptEval interrupts in-flight rules evaluations
 // within the group. It is expected that g.evalCancel
 // will be repopulated after the call.
-func (g *Group) interruptEval() {
+func (g *Group) InterruptEval() {
 	g.mu.RLock()
 	defer g.mu.RUnlock()
 
@@ -267,12 +282,13 @@ func (g *Group) interruptEval() {
 	}
 }
 
-func (g *Group) close() {
+// Close stops the group and it's rules, unregisters group metrics
+func (g *Group) Close() {
 	if g.doneCh == nil {
 		return
 	}
 	close(g.doneCh)
-	g.interruptEval()
+	g.InterruptEval()
 	<-g.finishedCh
 
 	g.metrics.iterationDuration.Unregister()
@@ -280,19 +296,21 @@ func (g *Group) close() {
 	g.metrics.iterationMissed.Unregister()
 	g.metrics.iterationInterval.Unregister()
 	for _, rule := range g.Rules {
-		rule.Close()
+		rule.close()
 	}
 }
 
-var skipRandSleepOnGroupStart bool
+// SkipRandSleepOnGroupStart will skip random sleep delay in group first evaluation
+var SkipRandSleepOnGroupStart bool
 
-func (g *Group) start(ctx context.Context, nts func() []notifier.Notifier, rw *remotewrite.Client, rr datasource.QuerierBuilder) {
+// Start starts group's evaluation
+func (g *Group) Start(ctx context.Context, nts func() []notifier.Notifier, rw remotewrite.RWClient, rr datasource.QuerierBuilder) {
 	defer func() { close(g.finishedCh) }()
 
 	evalTS := time.Now()
 	// sleep random duration to spread group rules evaluation
 	// over time in order to reduce load on datasource.
-	if !skipRandSleepOnGroupStart {
+	if !SkipRandSleepOnGroupStart {
 		sleepBeforeStart := delayBeforeStart(evalTS, g.ID(), g.Interval, g.EvalOffset)
 		g.infof("will start in %v", sleepBeforeStart)
 
@@ -310,10 +328,10 @@ func (g *Group) start(ctx context.Context, nts func() []notifier.Notifier, rw *r
 	}
 
 	e := &executor{
-		rw:                       rw,
-		notifiers:                nts,
+		Rw:                       rw,
+		Notifiers:                nts,
 		notifierHeaders:          g.NotifierHeaders,
-		previouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label),
+		PreviouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label),
 	}
 
 	g.infof("started")
@@ -355,7 +373,7 @@ func (g *Group) start(ctx context.Context, nts func() []notifier.Notifier, rw *r
 	// restore the rules state after the first evaluation
 	// so only active alerts can be restored.
 	if rr != nil {
-		err := g.Restore(ctx, rr, evalTS, *remoteReadLookBack)
+		err := g.restore(ctx, rr, evalTS, *remoteReadLookBack)
 		if err != nil {
 			logger.Errorf("error while restoring ruleState for group %q: %s", g.Name, err)
 		}
@@ -409,6 +427,22 @@ func (g *Group) start(ctx context.Context, nts func() []notifier.Notifier, rw *r
 	}
 }
 
+// UpdateWith inserts new group to updateCh
+func (g *Group) UpdateWith(new *Group) {
+	g.updateCh <- new
+}
+
+// DeepCopy returns a deep copy of group
+func (g *Group) DeepCopy() *Group {
+	g.mu.RLock()
+	data, _ := json.Marshal(g)
+	g.mu.RUnlock()
+	newG := Group{}
+	_ = json.Unmarshal(data, &newG)
+	newG.Rules = g.Rules
+	return &newG
+}
+
 // delayBeforeStart returns a duration on the interval between [ts..ts+interval].
 // delayBeforeStart accounts for `offset`, so returned duration should be always
 // bigger than the `offset`.
@@ -438,6 +472,89 @@ func (g *Group) infof(format string, args ...interface{}) {
 		g.Name, msg, g.Interval, g.EvalOffset, g.Concurrency)
 }
 
+// Replay performs group replay
+func (g *Group) Replay(start, end time.Time, rw remotewrite.RWClient, maxDataPoint, replayRuleRetryAttempts int, replayDelay time.Duration, disableProgressBar bool) int {
+	var total int
+	step := g.Interval * time.Duration(maxDataPoint)
+	ri := rangeIterator{start: start, end: end, step: step}
+	iterations := int(end.Sub(start)/step) + 1
+	fmt.Printf("\nGroup %q"+
+		"\ninterval: \t%v"+
+		"\nrequests to make: \t%d"+
+		"\nmax range per request: \t%v\n",
+		g.Name, g.Interval, iterations, step)
+	if g.Limit > 0 {
+		fmt.Printf("\nPlease note, `limit: %d` param has no effect during replay.\n",
+			g.Limit)
+	}
+	for _, rule := range g.Rules {
+		fmt.Printf("> Rule %q (ID: %d)\n", rule, rule.ID())
+		var bar *pb.ProgressBar
+		if !disableProgressBar {
+			bar = pb.StartNew(iterations)
+		}
+		ri.reset()
+		for ri.next() {
+			n, err := replayRule(rule, ri.s, ri.e, rw, replayRuleRetryAttempts)
+			if err != nil {
+				logger.Fatalf("rule %q: %s", rule, err)
+			}
+			total += n
+			if bar != nil {
+				bar.Increment()
+			}
+		}
+		if bar != nil {
+			bar.Finish()
+		}
+		// sleep to let remote storage to flush data on-disk
+		// so chained rules could be calculated correctly
+		time.Sleep(replayDelay)
+	}
+	return total
+}
+
+// ExecOnce evaluates all the rules under group for once with given timestamp.
+func (g *Group) ExecOnce(ctx context.Context, nts func() []notifier.Notifier, rw remotewrite.RWClient, evalTS time.Time) chan error {
+	e := &executor{
+		Rw:                       rw,
+		Notifiers:                nts,
+		notifierHeaders:          g.NotifierHeaders,
+		PreviouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label),
+	}
+	if len(g.Rules) < 1 {
+		return nil
+	}
+	resolveDuration := getResolveDuration(g.Interval, *resendDelay, *maxResolveDuration)
+	return e.execConcurrently(ctx, g.Rules, evalTS, g.Concurrency, resolveDuration, g.Limit)
+}
+
+type rangeIterator struct {
+	step       time.Duration
+	start, end time.Time
+
+	iter int
+	s, e time.Time
+}
+
+func (ri *rangeIterator) reset() {
+	ri.iter = 0
+	ri.s, ri.e = time.Time{}, time.Time{}
+}
+
+func (ri *rangeIterator) next() bool {
+	ri.s = ri.start.Add(ri.step * time.Duration(ri.iter))
+	if !ri.end.After(ri.s) {
+		return false
+	}
+	ri.e = ri.s.Add(ri.step)
+	if ri.e.After(ri.end) {
+		ri.e = ri.end
+	}
+	ri.iter++
+	return true
+}
+
 // getResolveDuration returns the duration after which firing alert
 // can be considered as resolved.
 func getResolveDuration(groupInterval, delta, maxDuration time.Duration) time.Duration {
@@ -477,20 +594,22 @@ func (g *Group) adjustReqTimestamp(timestamp time.Time) time.Time {
 	return timestamp
 }
 
+// executor contains group's notify and rw configs
 type executor struct {
-	notifiers       func() []notifier.Notifier
+	Notifiers       func() []notifier.Notifier
 	notifierHeaders map[string]string
 
-	rw *remotewrite.Client
+	Rw remotewrite.RWClient
 
 	previouslySentSeriesToRWMu sync.Mutex
-	// previouslySentSeriesToRW stores series sent to RW on previous iteration
+	// PreviouslySentSeriesToRW stores series sent to RW on previous iteration
 	// map[ruleID]map[ruleLabels][]prompb.Label
 	// where `ruleID` is ID of the Rule within a Group
 	// and `ruleLabels` is []prompb.Label marshalled to a string
-	previouslySentSeriesToRW map[uint64]map[string][]prompbmarshal.Label
+	PreviouslySentSeriesToRW map[uint64]map[string][]prompbmarshal.Label
 }
 
+// execConcurrently executes rules concurrently if concurrency>1
 func (e *executor) execConcurrently(ctx context.Context, rules []Rule, ts time.Time, concurrency int, resolveDuration time.Duration, limit int) chan error {
 	res := make(chan error, len(rules))
 	if concurrency == 1 {
@@ -505,14 +624,14 @@ func (e *executor) execConcurrently(ctx context.Context, rules []Rule, ts time.T
 	sem := make(chan struct{}, concurrency)
 	go func() {
 		wg := sync.WaitGroup{}
-		for _, rule := range rules {
+		for _, r := range rules {
 			sem <- struct{}{}
 			wg.Add(1)
 			go func(r Rule) {
 				res <- e.exec(ctx, r, ts, resolveDuration, limit)
 				<-sem
 				wg.Done()
-			}(rule)
+			}(r)
 		}
 		wg.Wait()
 		close(res)
@@ -530,10 +649,10 @@ var (
 	remoteWriteTotal  = metrics.NewCounter(`vmalert_remotewrite_total`)
 )
 
-func (e *executor) exec(ctx context.Context, rule Rule, ts time.Time, resolveDuration time.Duration, limit int) error {
+func (e *executor) exec(ctx context.Context, r Rule, ts time.Time, resolveDuration time.Duration, limit int) error {
 	execTotal.Inc()
 
-	tss, err := rule.Exec(ctx, ts, limit)
+	tss, err := r.exec(ctx, ts, limit)
 	if err != nil {
 		if errors.Is(err, context.Canceled) {
 			// the context can be cancelled on graceful shutdown
@@ -541,17 +660,17 @@ func (e *executor) exec(ctx context.Context, rule Rule, ts time.Time, resolveDur
 			return nil
 		}
 		execErrors.Inc()
-		return fmt.Errorf("rule %q: failed to execute: %w", rule, err)
+		return fmt.Errorf("rule %q: failed to execute: %w", r, err)
 	}
 
-	if e.rw != nil {
+	if e.Rw != nil {
 		pushToRW := func(tss []prompbmarshal.TimeSeries) error {
 			var lastErr error
 			for _, ts := range tss {
 				remoteWriteTotal.Inc()
-				if err := e.rw.Push(ts); err != nil {
+				if err := e.Rw.Push(ts); err != nil {
 					remoteWriteErrors.Inc()
-					lastErr = fmt.Errorf("rule %q: remote write failure: %w", rule, err)
+					lastErr = fmt.Errorf("rule %q: remote write failure: %w", r, err)
 				}
 			}
 			return lastErr
@@ -560,13 +679,13 @@ func (e *executor) exec(ctx context.Context, rule Rule, ts time.Time, resolveDur
 			return err
 		}
 
-		staleSeries := e.getStaleSeries(rule, tss, ts)
+		staleSeries := e.getStaleSeries(r, tss, ts)
 		if err := pushToRW(staleSeries); err != nil {
 			return err
 		}
 	}
 
-	ar, ok := rule.(*AlertingRule)
+	ar, ok := r.(*AlertingRule)
 	if !ok {
 		return nil
 	}
@@ -578,11 +697,11 @@ func (e *executor) exec(ctx context.Context, rule Rule, ts time.Time, resolveDur
 
 	wg := sync.WaitGroup{}
 	errGr := new(utils.ErrGroup)
-	for _, nt := range e.notifiers() {
+	for _, nt := range e.Notifiers() {
 		wg.Add(1)
 		go func(nt notifier.Notifier) {
 			if err := nt.Send(ctx, alerts, e.notifierHeaders); err != nil {
-				errGr.Add(fmt.Errorf("rule %q: failed to send alerts to addr %q: %w", rule, nt.Addr(), err))
+				errGr.Add(fmt.Errorf("rule %q: failed to send alerts to addr %q: %w", r, nt.Addr(), err))
 			}
 			wg.Done()
 		}(nt)
@@ -592,7 +711,7 @@ func (e *executor) exec(ctx context.Context, rule Rule, ts time.Time, resolveDur
 }
 
 // getStaledSeries checks whether there are stale series from previously sent ones.
-func (e *executor) getStaleSeries(rule Rule, tss []prompbmarshal.TimeSeries, timestamp time.Time) []prompbmarshal.TimeSeries {
+func (e *executor) getStaleSeries(r Rule, tss []prompbmarshal.TimeSeries, timestamp time.Time) []prompbmarshal.TimeSeries {
 	ruleLabels := make(map[string][]prompbmarshal.Label, len(tss))
 	for _, ts := range tss {
 		// convert labels to strings so we can compare with previously sent series
@@ -600,11 +719,11 @@ func (e *executor) getStaleSeries(rule Rule, tss []prompbmarshal.TimeSeries, tim
 		ruleLabels[key] = ts.Labels
 	}
 
-	rID := rule.ID()
+	rID := r.ID()
 	var staleS []prompbmarshal.TimeSeries
 	// check whether there are series which disappeared and need to be marked as stale
 	e.previouslySentSeriesToRWMu.Lock()
-	for key, labels := range e.previouslySentSeriesToRW[rID] {
+	for key, labels := range e.PreviouslySentSeriesToRW[rID] {
 		if _, ok := ruleLabels[key]; ok {
 			continue
 		}
@@ -613,7 +732,7 @@ func (e *executor) getStaleSeries(rule Rule, tss []prompbmarshal.TimeSeries, tim
 		staleS = append(staleS, ss)
 	}
 	// set previous series to current
-	e.previouslySentSeriesToRW[rID] = ruleLabels
+	e.PreviouslySentSeriesToRW[rID] = ruleLabels
 	e.previouslySentSeriesToRWMu.Unlock()
 
 	return staleS
@@ -631,14 +750,14 @@ func (e *executor) purgeStaleSeries(activeRules []Rule) {
 
 	for _, rule := range activeRules {
 		id := rule.ID()
-		prev, ok := e.previouslySentSeriesToRW[id]
+		prev, ok := e.PreviouslySentSeriesToRW[id]
 		if ok {
 			// keep previous series for staleness detection
 			newPreviouslySentSeriesToRW[id] = prev
 		}
 	}
-	e.previouslySentSeriesToRW = nil
-	e.previouslySentSeriesToRW = newPreviouslySentSeriesToRW
+	e.PreviouslySentSeriesToRW = nil
+	e.PreviouslySentSeriesToRW = newPreviouslySentSeriesToRW
 
 	e.previouslySentSeriesToRWMu.Unlock()
 }
diff --git a/app/vmalert/group_test.go b/app/vmalert/rule/group_test.go
similarity index 74%
rename from app/vmalert/group_test.go
rename to app/vmalert/rule/group_test.go
index 4b687d205..f0342d120 100644
--- a/app/vmalert/group_test.go
+++ b/app/vmalert/rule/group_test.go
@@ -1,17 +1,22 @@
-package main
+package rule
 
 import (
 	"context"
 	"fmt"
 	"math"
+	"os"
 	"reflect"
 	"sort"
 	"testing"
 	"time"
 
+	"gopkg.in/yaml.v2"
+
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/templates"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/decimal"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promutils"
@@ -20,7 +25,15 @@ import (
 func init() {
 	// Disable rand sleep on group start during tests in order to speed up test execution.
 	// Rand sleep is needed only in prod code.
-	skipRandSleepOnGroupStart = true
+	SkipRandSleepOnGroupStart = true
+}
+
+func TestMain(m *testing.M) {
+	if err := templates.Load([]string{}, true); err != nil {
+		fmt.Println("failed to load template for test")
+		os.Exit(1)
+	}
+	os.Exit(m.Run())
 }
 
 func TestUpdateWith(t *testing.T) {
@@ -138,7 +151,7 @@ func TestUpdateWith(t *testing.T) {
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
 			g := &Group{Name: "test"}
-			qb := &fakeQuerier{}
+			qb := &datasource.FakeQuerier{}
 			for _, r := range tc.currentRules {
 				r.ID = config.HashRule(r)
 				g.Rules = append(g.Rules, g.newRule(qb, r))
@@ -170,7 +183,7 @@ func TestUpdateWith(t *testing.T) {
 				if got.ID() != want.ID() {
 					t.Fatalf("expected to have rule %q; got %q", want, got)
 				}
-				if err := compareRules(t, got, want); err != nil {
+				if err := CompareRules(t, got, want); err != nil {
 					t.Fatalf("comparison error: %s", err)
 				}
 			}
@@ -179,17 +192,31 @@ func TestUpdateWith(t *testing.T) {
 }
 
 func TestGroupStart(t *testing.T) {
-	// TODO: make parsing from string instead of file
-	groups, err := config.Parse([]string{"config/testdata/rules/rules1-good.rules"}, notifier.ValidateTemplates, true)
+	const (
+		rules = `
+  - name: groupTest
+    rules:
+      - alert: VMRows
+        for: 1ms
+        expr: vm_rows > 0
+        labels:
+          label: bar
+          host: "{{ $labels.instance }}"
+        annotations:
+          summary: "{{ $value }}"
+`
+	)
+	var groups []config.Group
+	err := yaml.Unmarshal([]byte(rules), &groups)
 	if err != nil {
 		t.Fatalf("failed to parse rules: %s", err)
 	}
 
-	fs := &fakeQuerier{}
-	fn := &fakeNotifier{}
+	fs := &datasource.FakeQuerier{}
+	fn := &notifier.FakeNotifier{}
 
 	const evalInterval = time.Millisecond
-	g := newGroup(groups[0], fs, evalInterval, map[string]string{"cluster": "east-1"})
+	g := NewGroup(groups[0], fs, evalInterval, map[string]string{"cluster": "east-1"})
 	g.Concurrency = 2
 
 	const inst1, inst2, job = "foo", "bar", "baz"
@@ -204,7 +231,7 @@ func TestGroupStart(t *testing.T) {
 	alert1.State = notifier.StateFiring
 	// add external label
 	alert1.Labels["cluster"] = "east-1"
-	// add rule labels - see config/testdata/rules1-good.rules
+	// add rule labels
 	alert1.Labels["label"] = "bar"
 	alert1.Labels["host"] = inst1
 	// add service labels
@@ -219,7 +246,7 @@ func TestGroupStart(t *testing.T) {
 	alert2.State = notifier.StateFiring
 	// add external label
 	alert2.Labels["cluster"] = "east-1"
-	// add rule labels - see config/testdata/rules1-good.rules
+	// add rule labels
 	alert2.Labels["label"] = "bar"
 	alert2.Labels["host"] = inst2
 	// add service labels
@@ -228,40 +255,40 @@ func TestGroupStart(t *testing.T) {
 	alert2.ID = hash(alert2.Labels)
 
 	finished := make(chan struct{})
-	fs.add(m1)
-	fs.add(m2)
+	fs.Add(m1)
+	fs.Add(m2)
 	go func() {
-		g.start(context.Background(), func() []notifier.Notifier { return []notifier.Notifier{fn} }, nil, fs)
+		g.Start(context.Background(), func() []notifier.Notifier { return []notifier.Notifier{fn} }, nil, fs)
 		close(finished)
 	}()
 
 	// wait for multiple evals
 	time.Sleep(20 * evalInterval)
 
-	gotAlerts := fn.getAlerts()
+	gotAlerts := fn.GetAlerts()
 	expectedAlerts := []notifier.Alert{*alert1, *alert2}
 	compareAlerts(t, expectedAlerts, gotAlerts)
 
-	gotAlertsNum := fn.getCounter()
+	gotAlertsNum := fn.GetCounter()
 	if gotAlertsNum < len(expectedAlerts)*2 {
 		t.Fatalf("expected to receive at least %d alerts; got %d instead",
 			len(expectedAlerts)*2, gotAlertsNum)
 	}
 
 	// reset previous data
-	fs.reset()
+	fs.Reset()
 	// and set only one datapoint for response
-	fs.add(m1)
+	fs.Add(m1)
 
 	// wait for multiple evals
 	time.Sleep(20 * evalInterval)
 
-	gotAlerts = fn.getAlerts()
+	gotAlerts = fn.GetAlerts()
 	alert2.State = notifier.StateInactive
 	expectedAlerts = []notifier.Alert{*alert1, *alert2}
 	compareAlerts(t, expectedAlerts, gotAlerts)
 
-	g.close()
+	g.Close()
 	<-finished
 }
 
@@ -294,15 +321,15 @@ func TestResolveDuration(t *testing.T) {
 func TestGetStaleSeries(t *testing.T) {
 	ts := time.Now()
 	e := &executor{
-		previouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label),
+		PreviouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label),
 	}
-	f := func(rule Rule, labels, expLabels [][]prompbmarshal.Label) {
+	f := func(r Rule, labels, expLabels [][]prompbmarshal.Label) {
 		t.Helper()
 		var tss []prompbmarshal.TimeSeries
 		for _, l := range labels {
 			tss = append(tss, newTimeSeriesPB([]float64{1}, []int64{ts.Unix()}, l))
 		}
-		staleS := e.getStaleSeries(rule, tss, ts)
+		staleS := e.getStaleSeries(r, tss, ts)
 		if staleS == nil && expLabels == nil {
 			return
 		}
@@ -387,7 +414,7 @@ func TestPurgeStaleSeries(t *testing.T) {
 	f := func(curRules, newRules, expStaleRules []Rule) {
 		t.Helper()
 		e := &executor{
-			previouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label),
+			PreviouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label),
 		}
 		// seed executor with series for
 		// current rules
@@ -397,13 +424,13 @@ func TestPurgeStaleSeries(t *testing.T) {
 
 		e.purgeStaleSeries(newRules)
 
-		if len(e.previouslySentSeriesToRW) != len(expStaleRules) {
+		if len(e.PreviouslySentSeriesToRW) != len(expStaleRules) {
 			t.Fatalf("expected to get %d stale series, got %d",
-				len(expStaleRules), len(e.previouslySentSeriesToRW))
+				len(expStaleRules), len(e.PreviouslySentSeriesToRW))
 		}
 
 		for _, exp := range expStaleRules {
-			if _, ok := e.previouslySentSeriesToRW[exp.ID()]; !ok {
+			if _, ok := e.PreviouslySentSeriesToRW[exp.ID()]; !ok {
 				t.Fatalf("expected to have rule %d; got nil instead", exp.ID())
 			}
 		}
@@ -438,17 +465,17 @@ func TestPurgeStaleSeries(t *testing.T) {
 }
 
 func TestFaultyNotifier(t *testing.T) {
-	fq := &fakeQuerier{}
-	fq.add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "bar"))
+	fq := &datasource.FakeQuerier{}
+	fq.Add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "bar"))
 
 	r := newTestAlertingRule("instant", 0)
 	r.q = fq
 
-	fn := &fakeNotifier{}
+	fn := &notifier.FakeNotifier{}
 	e := &executor{
-		notifiers: func() []notifier.Notifier {
+		Notifiers: func() []notifier.Notifier {
 			return []notifier.Notifier{
-				&faultyNotifier{},
+				&notifier.FaultyNotifier{},
 				fn,
 			}
 		},
@@ -464,7 +491,7 @@ func TestFaultyNotifier(t *testing.T) {
 	tn := time.Now()
 	deadline := tn.Add(delay / 2)
 	for {
-		if fn.getCounter() > 0 {
+		if fn.GetCounter() > 0 {
 			return
 		}
 		if tn.After(deadline) {
@@ -477,18 +504,18 @@ func TestFaultyNotifier(t *testing.T) {
 }
 
 func TestFaultyRW(t *testing.T) {
-	fq := &fakeQuerier{}
-	fq.add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "bar"))
+	fq := &datasource.FakeQuerier{}
+	fq.Add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "bar"))
 
 	r := &RecordingRule{
 		Name:  "test",
-		state: newRuleState(10),
 		q:     fq,
+		state: &ruleState{entries: make([]StateEntry, 10)},
 	}
 
 	e := &executor{
-		rw:                       &remotewrite.Client{},
-		previouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label),
+		Rw:                       &remotewrite.Client{},
+		PreviouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label),
 	}
 
 	err := e.exec(context.Background(), r, time.Now(), 0, 10)
@@ -498,23 +525,38 @@ func TestFaultyRW(t *testing.T) {
 }
 
 func TestCloseWithEvalInterruption(t *testing.T) {
-	groups, err := config.Parse([]string{"config/testdata/rules/rules1-good.rules"}, notifier.ValidateTemplates, true)
+	const (
+		rules = `
+  - name: groupTest
+    rules:
+      - alert: VMRows
+        for: 1ms
+        expr: vm_rows > 0
+        labels:
+          label: bar
+          host: "{{ $labels.instance }}"
+        annotations:
+          summary: "{{ $value }}"
+`
+	)
+	var groups []config.Group
+	err := yaml.Unmarshal([]byte(rules), &groups)
 	if err != nil {
 		t.Fatalf("failed to parse rules: %s", err)
 	}
 
 	const delay = time.Second * 2
-	fq := &fakeQuerierWithDelay{delay: delay}
+	fq := &datasource.FakeQuerierWithDelay{Delay: delay}
 
 	const evalInterval = time.Millisecond
-	g := newGroup(groups[0], fq, evalInterval, nil)
+	g := NewGroup(groups[0], fq, evalInterval, nil)
 
-	go g.start(context.Background(), nil, nil, nil)
+	go g.Start(context.Background(), nil, nil, nil)
 
 	time.Sleep(evalInterval * 20)
 
 	go func() {
-		g.close()
+		g.Close()
 	}()
 
 	deadline := time.Tick(delay / 2)
@@ -637,3 +679,81 @@ func TestGetPrometheusReqTimestamp(t *testing.T) {
 		}
 	}
 }
+
+func TestRangeIterator(t *testing.T) {
+	testCases := []struct {
+		ri     rangeIterator
+		result [][2]time.Time
+	}{
+		{
+			ri: rangeIterator{
+				start: parseTime(t, "2021-01-01T12:00:00.000Z"),
+				end:   parseTime(t, "2021-01-01T12:30:00.000Z"),
+				step:  5 * time.Minute,
+			},
+			result: [][2]time.Time{
+				{parseTime(t, "2021-01-01T12:00:00.000Z"), parseTime(t, "2021-01-01T12:05:00.000Z")},
+				{parseTime(t, "2021-01-01T12:05:00.000Z"), parseTime(t, "2021-01-01T12:10:00.000Z")},
+				{parseTime(t, "2021-01-01T12:10:00.000Z"), parseTime(t, "2021-01-01T12:15:00.000Z")},
+				{parseTime(t, "2021-01-01T12:15:00.000Z"), parseTime(t, "2021-01-01T12:20:00.000Z")},
+				{parseTime(t, "2021-01-01T12:20:00.000Z"), parseTime(t, "2021-01-01T12:25:00.000Z")},
+				{parseTime(t, "2021-01-01T12:25:00.000Z"), parseTime(t, "2021-01-01T12:30:00.000Z")},
+			},
+		},
+		{
+			ri: rangeIterator{
+				start: parseTime(t, "2021-01-01T12:00:00.000Z"),
+				end:   parseTime(t, "2021-01-01T12:30:00.000Z"),
+				step:  45 * time.Minute,
+			},
+			result: [][2]time.Time{
+				{parseTime(t, "2021-01-01T12:00:00.000Z"), parseTime(t, "2021-01-01T12:30:00.000Z")},
+				{parseTime(t, "2021-01-01T12:30:00.000Z"), parseTime(t, "2021-01-01T12:30:00.000Z")},
+			},
+		},
+		{
+			ri: rangeIterator{
+				start: parseTime(t, "2021-01-01T12:00:12.000Z"),
+				end:   parseTime(t, "2021-01-01T12:00:17.000Z"),
+				step:  time.Second,
+			},
+			result: [][2]time.Time{
+				{parseTime(t, "2021-01-01T12:00:12.000Z"), parseTime(t, "2021-01-01T12:00:13.000Z")},
+				{parseTime(t, "2021-01-01T12:00:13.000Z"), parseTime(t, "2021-01-01T12:00:14.000Z")},
+				{parseTime(t, "2021-01-01T12:00:14.000Z"), parseTime(t, "2021-01-01T12:00:15.000Z")},
+				{parseTime(t, "2021-01-01T12:00:15.000Z"), parseTime(t, "2021-01-01T12:00:16.000Z")},
+				{parseTime(t, "2021-01-01T12:00:16.000Z"), parseTime(t, "2021-01-01T12:00:17.000Z")},
+			},
+		},
+	}
+
+	for i, tc := range testCases {
+		t.Run(fmt.Sprintf("case %d", i), func(t *testing.T) {
+			var j int
+			for tc.ri.next() {
+				if len(tc.result) < j+1 {
+					t.Fatalf("unexpected result for iterator on step %d: %v - %v",
+						j, tc.ri.s, tc.ri.e)
+				}
+				s, e := tc.ri.s, tc.ri.e
+				expS, expE := tc.result[j][0], tc.result[j][1]
+				if s != expS {
+					t.Fatalf("expected to get start=%v; got %v", expS, s)
+				}
+				if e != expE {
+					t.Fatalf("expected to get end=%v; got %v", expE, e)
+				}
+				j++
+			}
+		})
+	}
+}
+
+func parseTime(t *testing.T, s string) time.Time {
+	t.Helper()
+	tt, err := time.Parse("2006-01-02T15:04:05.000Z", s)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return tt
+}
diff --git a/app/vmalert/recording.go b/app/vmalert/rule/recording.go
similarity index 68%
rename from app/vmalert/recording.go
rename to app/vmalert/rule/recording.go
index fd137d05e..fc25c903b 100644
--- a/app/vmalert/recording.go
+++ b/app/vmalert/rule/recording.go
@@ -1,4 +1,4 @@
-package main
+package rule
 
 import (
 	"context"
@@ -49,7 +49,8 @@ func (rr *RecordingRule) ID() uint64 {
 	return rr.RuleID
 }
 
-func newRecordingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rule) *RecordingRule {
+// NewRecordingRule creates a new RecordingRule
+func NewRecordingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rule) *RecordingRule {
 	rr := &RecordingRule{
 		Type:    group.Type,
 		RuleID:  cfg.ID,
@@ -66,17 +67,22 @@ func newRecordingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rul
 		}),
 	}
 
+	entrySize := *ruleUpdateEntriesLimit
 	if cfg.UpdateEntriesLimit != nil {
-		rr.state = newRuleState(*cfg.UpdateEntriesLimit)
-	} else {
-		rr.state = newRuleState(*ruleUpdateEntriesLimit)
+		entrySize = *cfg.UpdateEntriesLimit
+	}
+	if entrySize < 1 {
+		entrySize = 1
+	}
+	rr.state = &ruleState{
+		entries: make([]StateEntry, entrySize),
 	}
 
 	labels := fmt.Sprintf(`recording=%q, group=%q, id="%d"`, rr.Name, group.Name, rr.ID())
 	rr.metrics.errors = utils.GetOrCreateGauge(fmt.Sprintf(`vmalert_recording_rules_error{%s}`, labels),
 		func() float64 {
 			e := rr.state.getLast()
-			if e.err == nil {
+			if e.Err == nil {
 				return 0
 			}
 			return 1
@@ -84,21 +90,21 @@ func newRecordingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rul
 	rr.metrics.samples = utils.GetOrCreateGauge(fmt.Sprintf(`vmalert_recording_rules_last_evaluation_samples{%s}`, labels),
 		func() float64 {
 			e := rr.state.getLast()
-			return float64(e.samples)
+			return float64(e.Samples)
 		})
 	return rr
 }
 
-// Close unregisters rule metrics
-func (rr *RecordingRule) Close() {
+// close unregisters rule metrics
+func (rr *RecordingRule) close() {
 	rr.metrics.errors.Unregister()
 	rr.metrics.samples.Unregister()
 }
 
-// ExecRange executes recording rule on the given time range similarly to Exec.
+// execRange executes recording rule on the given time range similarly to Exec.
 // It doesn't update internal states of the Rule and meant to be used just
 // to get time series for backfilling.
-func (rr *RecordingRule) ExecRange(ctx context.Context, start, end time.Time) ([]prompbmarshal.TimeSeries, error) {
+func (rr *RecordingRule) execRange(ctx context.Context, start, end time.Time) ([]prompbmarshal.TimeSeries, error) {
 	res, err := rr.q.QueryRange(ctx, rr.Expr, start, end)
 	if err != nil {
 		return nil, err
@@ -117,17 +123,17 @@ func (rr *RecordingRule) ExecRange(ctx context.Context, start, end time.Time) ([
 	return tss, nil
 }
 
-// Exec executes RecordingRule expression via the given Querier.
-func (rr *RecordingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]prompbmarshal.TimeSeries, error) {
+// exec executes RecordingRule expression via the given Querier.
+func (rr *RecordingRule) exec(ctx context.Context, ts time.Time, limit int) ([]prompbmarshal.TimeSeries, error) {
 	start := time.Now()
 	res, req, err := rr.q.Query(ctx, rr.Expr, ts)
-	curState := ruleStateEntry{
-		time:          start,
-		at:            ts,
-		duration:      time.Since(start),
-		samples:       len(res.Data),
-		seriesFetched: res.SeriesFetched,
-		curl:          requestToCurl(req),
+	curState := StateEntry{
+		Time:          start,
+		At:            ts,
+		Duration:      time.Since(start),
+		Samples:       len(res.Data),
+		SeriesFetched: res.SeriesFetched,
+		Curl:          requestToCurl(req),
 	}
 
 	defer func() {
@@ -135,15 +141,15 @@ func (rr *RecordingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]p
 	}()
 
 	if err != nil {
-		curState.err = fmt.Errorf("failed to execute query %q: %w", rr.Expr, err)
-		return nil, curState.err
+		curState.Err = fmt.Errorf("failed to execute query %q: %w", rr.Expr, err)
+		return nil, curState.Err
 	}
 
 	qMetrics := res.Data
 	numSeries := len(qMetrics)
 	if limit > 0 && numSeries > limit {
-		curState.err = fmt.Errorf("exec exceeded limit of %d with %d series", limit, numSeries)
-		return nil, curState.err
+		curState.Err = fmt.Errorf("exec exceeded limit of %d with %d series", limit, numSeries)
+		return nil, curState.Err
 	}
 
 	duplicates := make(map[string]struct{}, len(qMetrics))
@@ -152,8 +158,8 @@ func (rr *RecordingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]p
 		ts := rr.toTimeSeries(r)
 		key := stringifyLabels(ts)
 		if _, ok := duplicates[key]; ok {
-			curState.err = fmt.Errorf("original metric %v; resulting labels %q: %w", r, key, errDuplicate)
-			return nil, curState.err
+			curState.Err = fmt.Errorf("original metric %v; resulting labels %q: %w", r, key, errDuplicate)
+			return nil, curState.Err
 		}
 		duplicates[key] = struct{}{}
 		tss = append(tss, ts)
@@ -193,8 +199,8 @@ func (rr *RecordingRule) toTimeSeries(m datasource.Metric) prompbmarshal.TimeSer
 	return newTimeSeries(m.Values, m.Timestamps, labels)
 }
 
-// UpdateWith copies all significant fields.
-func (rr *RecordingRule) UpdateWith(r Rule) error {
+// updateWith copies all significant fields.
+func (rr *RecordingRule) updateWith(r Rule) error {
 	nr, ok := r.(*RecordingRule)
 	if !ok {
 		return fmt.Errorf("BUG: attempt to update recroding rule with wrong type %#v", r)
@@ -204,32 +210,3 @@ func (rr *RecordingRule) UpdateWith(r Rule) error {
 	rr.q = nr.q
 	return nil
 }
-
-// ToAPI returns Rule's representation in form
-// of APIRule
-func (rr *RecordingRule) ToAPI() APIRule {
-	lastState := rr.state.getLast()
-	r := APIRule{
-		Type:              "recording",
-		DatasourceType:    rr.Type.String(),
-		Name:              rr.Name,
-		Query:             rr.Expr,
-		Labels:            rr.Labels,
-		LastEvaluation:    lastState.time,
-		EvaluationTime:    lastState.duration.Seconds(),
-		Health:            "ok",
-		LastSamples:       lastState.samples,
-		LastSeriesFetched: lastState.seriesFetched,
-		MaxUpdates:        rr.state.size(),
-		Updates:           rr.state.getAll(),
-
-		// encode as strings to avoid rounding
-		ID:      fmt.Sprintf("%d", rr.ID()),
-		GroupID: fmt.Sprintf("%d", rr.GroupID),
-	}
-	if lastState.err != nil {
-		r.LastError = lastState.err.Error()
-		r.Health = "err"
-	}
-	return r
-}
diff --git a/app/vmalert/recording_test.go b/app/vmalert/rule/recording_test.go
similarity index 86%
rename from app/vmalert/recording_test.go
rename to app/vmalert/rule/recording_test.go
index 2cc842f1b..287bb065c 100644
--- a/app/vmalert/recording_test.go
+++ b/app/vmalert/rule/recording_test.go
@@ -1,4 +1,4 @@
-package main
+package rule
 
 import (
 	"context"
@@ -56,10 +56,12 @@ func TestRecordingRule_Exec(t *testing.T) {
 				Name: "job:foo",
 				Labels: map[string]string{
 					"source": "test",
-				}},
+				},
+			},
 			[]datasource.Metric{
 				metricWithValueAndLabels(t, 2, "__name__", "foo", "job", "foo"),
-				metricWithValueAndLabels(t, 1, "__name__", "bar", "job", "bar")},
+				metricWithValueAndLabels(t, 1, "__name__", "bar", "job", "bar"),
+			},
 			[]prompbmarshal.TimeSeries{
 				newTimeSeries([]float64{2}, []int64{timestamp.UnixNano()}, map[string]string{
 					"__name__": "job:foo",
@@ -76,11 +78,11 @@ func TestRecordingRule_Exec(t *testing.T) {
 	}
 	for _, tc := range testCases {
 		t.Run(tc.rule.Name, func(t *testing.T) {
-			fq := &fakeQuerier{}
-			fq.add(tc.metrics...)
+			fq := &datasource.FakeQuerier{}
+			fq.Add(tc.metrics...)
 			tc.rule.q = fq
-			tc.rule.state = newRuleState(10)
-			tss, err := tc.rule.Exec(context.TODO(), time.Now(), 0)
+			tc.rule.state = &ruleState{entries: make([]StateEntry, 10)}
+			tss, err := tc.rule.exec(context.TODO(), time.Now(), 0)
 			if err != nil {
 				t.Fatalf("unexpected Exec err: %s", err)
 			}
@@ -141,7 +143,8 @@ func TestRecordingRule_ExecRange(t *testing.T) {
 			}},
 			[]datasource.Metric{
 				metricWithValueAndLabels(t, 2, "__name__", "foo", "job", "foo"),
-				metricWithValueAndLabels(t, 1, "__name__", "bar", "job", "bar")},
+				metricWithValueAndLabels(t, 1, "__name__", "bar", "job", "bar"),
+			},
 			[]prompbmarshal.TimeSeries{
 				newTimeSeries([]float64{2}, []int64{timestamp.UnixNano()}, map[string]string{
 					"__name__": "job:foo",
@@ -158,10 +161,10 @@ func TestRecordingRule_ExecRange(t *testing.T) {
 	}
 	for _, tc := range testCases {
 		t.Run(tc.rule.Name, func(t *testing.T) {
-			fq := &fakeQuerier{}
-			fq.add(tc.metrics...)
+			fq := &datasource.FakeQuerier{}
+			fq.Add(tc.metrics...)
 			tc.rule.q = fq
-			tss, err := tc.rule.ExecRange(context.TODO(), time.Now(), time.Now())
+			tss, err := tc.rule.execRange(context.TODO(), time.Now(), time.Now())
 			if err != nil {
 				t.Fatalf("unexpected Exec err: %s", err)
 			}
@@ -198,15 +201,15 @@ func TestRecordingRuleLimit(t *testing.T) {
 		metricWithValuesAndLabels(t, []float64{2, 3}, "__name__", "bar", "job", "bar"),
 		metricWithValuesAndLabels(t, []float64{4, 5, 6}, "__name__", "baz", "job", "baz"),
 	}
-	rule := &RecordingRule{Name: "job:foo", state: newRuleState(10), Labels: map[string]string{
+	rule := &RecordingRule{Name: "job:foo", state: &ruleState{entries: make([]StateEntry, 10)}, Labels: map[string]string{
 		"source": "test_limit",
 	}}
 	var err error
 	for _, testCase := range testCases {
-		fq := &fakeQuerier{}
-		fq.add(testMetrics...)
+		fq := &datasource.FakeQuerier{}
+		fq.Add(testMetrics...)
 		rule.q = fq
-		_, err = rule.Exec(context.TODO(), timestamp, testCase.limit)
+		_, err = rule.exec(context.TODO(), timestamp, testCase.limit)
 		if err != nil && !strings.EqualFold(err.Error(), testCase.err) {
 			t.Fatal(err)
 		}
@@ -215,18 +218,17 @@ func TestRecordingRuleLimit(t *testing.T) {
 
 func TestRecordingRule_ExecNegative(t *testing.T) {
 	rr := &RecordingRule{
-		Name:  "job:foo",
-		state: newRuleState(10),
+		Name: "job:foo",
 		Labels: map[string]string{
 			"job": "test",
 		},
+		state: &ruleState{entries: make([]StateEntry, 10)},
 	}
-
-	fq := &fakeQuerier{}
+	fq := &datasource.FakeQuerier{}
 	expErr := "connection reset by peer"
-	fq.setErr(errors.New(expErr))
+	fq.SetErr(errors.New(expErr))
 	rr.q = fq
-	_, err := rr.Exec(context.TODO(), time.Now(), 0)
+	_, err := rr.exec(context.TODO(), time.Now(), 0)
 	if err == nil {
 		t.Fatalf("expected to get err; got nil")
 	}
@@ -234,14 +236,14 @@ func TestRecordingRule_ExecNegative(t *testing.T) {
 		t.Fatalf("expected to get err %q; got %q insterad", expErr, err)
 	}
 
-	fq.reset()
+	fq.Reset()
 
 	// add metrics which differs only by `job` label
 	// which will be overridden by rule
-	fq.add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "foo"))
-	fq.add(metricWithValueAndLabels(t, 2, "__name__", "foo", "job", "bar"))
+	fq.Add(metricWithValueAndLabels(t, 1, "__name__", "foo", "job", "foo"))
+	fq.Add(metricWithValueAndLabels(t, 2, "__name__", "foo", "job", "bar"))
 
-	_, err = rr.Exec(context.TODO(), time.Now(), 0)
+	_, err = rr.exec(context.TODO(), time.Now(), 0)
 	if err == nil {
 		t.Fatalf("expected to get err; got nil")
 	}
diff --git a/app/vmalert/rule/rule.go b/app/vmalert/rule/rule.go
new file mode 100644
index 000000000..6240fb430
--- /dev/null
+++ b/app/vmalert/rule/rule.go
@@ -0,0 +1,174 @@
+package rule
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
+)
+
+// Rule represents alerting or recording rule
+// that has unique ID, can be Executed and
+// updated with other Rule.
+type Rule interface {
+	// ID returns unique ID that may be used for
+	// identifying this Rule among others.
+	ID() uint64
+	// exec executes the rule with given context at the given timestamp and limit.
+	// returns an err if number of resulting time series exceeds the limit.
+	exec(ctx context.Context, ts time.Time, limit int) ([]prompbmarshal.TimeSeries, error)
+	// execRange executes the rule on the given time range.
+	execRange(ctx context.Context, start, end time.Time) ([]prompbmarshal.TimeSeries, error)
+	// updateWith performs modification of current Rule
+	// with fields of the given Rule.
+	updateWith(Rule) error
+	// close performs the shutdown procedures for rule
+	// such as metrics unregister
+	close()
+}
+
+var errDuplicate = errors.New("result contains metrics with the same labelset after applying rule labels. See https://docs.victoriametrics.com/vmalert.html#series-with-the-same-labelset for details")
+
+type ruleState struct {
+	sync.RWMutex
+	entries []StateEntry
+	cur     int
+}
+
+// StateEntry stores rule's execution states
+type StateEntry struct {
+	// stores last moment of time rule.Exec was called
+	Time time.Time
+	// stores the timesteamp with which rule.Exec was called
+	At time.Time
+	// stores the duration of the last rule.Exec call
+	Duration time.Duration
+	// stores last error that happened in Exec func
+	// resets on every successful Exec
+	// may be used as Health ruleState
+	Err error
+	// stores the number of samples returned during
+	// the last evaluation
+	Samples int
+	// stores the number of time series fetched during
+	// the last evaluation.
+	// Is supported by VictoriaMetrics only, starting from v1.90.0
+	// If seriesFetched == nil, then this attribute was missing in
+	// datasource response (unsupported).
+	SeriesFetched *int
+	// stores the curl command reflecting the HTTP request used during rule.Exec
+	Curl string
+}
+
+// GetLastEntry returns latest stateEntry of rule
+func GetLastEntry(r Rule) StateEntry {
+	if rule, ok := r.(*AlertingRule); ok {
+		return rule.state.getLast()
+	}
+	if rule, ok := r.(*RecordingRule); ok {
+		return rule.state.getLast()
+	}
+	return StateEntry{}
+}
+
+// GetRuleStateSize returns size of rule stateEntry
+func GetRuleStateSize(r Rule) int {
+	if rule, ok := r.(*AlertingRule); ok {
+		return rule.state.size()
+	}
+	if rule, ok := r.(*RecordingRule); ok {
+		return rule.state.size()
+	}
+	return 0
+}
+
+// GetAllRuleState returns rule entire stateEntries
+func GetAllRuleState(r Rule) []StateEntry {
+	if rule, ok := r.(*AlertingRule); ok {
+		return rule.state.getAll()
+	}
+	if rule, ok := r.(*RecordingRule); ok {
+		return rule.state.getAll()
+	}
+	return []StateEntry{}
+}
+
+func (s *ruleState) size() int {
+	s.RLock()
+	defer s.RUnlock()
+	return len(s.entries)
+}
+
+func (s *ruleState) getLast() StateEntry {
+	s.RLock()
+	defer s.RUnlock()
+	if len(s.entries) == 0 {
+		return StateEntry{}
+	}
+	return s.entries[s.cur]
+}
+
+func (s *ruleState) getAll() []StateEntry {
+	entries := make([]StateEntry, 0)
+
+	s.RLock()
+	defer s.RUnlock()
+
+	cur := s.cur
+	for {
+		e := s.entries[cur]
+		if !e.Time.IsZero() || !e.At.IsZero() {
+			entries = append(entries, e)
+		}
+		cur--
+		if cur < 0 {
+			cur = cap(s.entries) - 1
+		}
+		if cur == s.cur {
+			return entries
+		}
+	}
+}
+
+func (s *ruleState) add(e StateEntry) {
+	s.Lock()
+	defer s.Unlock()
+
+	s.cur++
+	if s.cur > cap(s.entries)-1 {
+		s.cur = 0
+	}
+	s.entries[s.cur] = e
+}
+
+func replayRule(r Rule, start, end time.Time, rw remotewrite.RWClient, replayRuleRetryAttempts int) (int, error) {
+	var err error
+	var tss []prompbmarshal.TimeSeries
+	for i := 0; i < replayRuleRetryAttempts; i++ {
+		tss, err = r.execRange(context.Background(), start, end)
+		if err == nil {
+			break
+		}
+		logger.Errorf("attempt %d to execute rule %q failed: %s", i+1, r, err)
+		time.Sleep(time.Second)
+	}
+	if err != nil { // means all attempts failed
+		return 0, err
+	}
+	if len(tss) < 1 {
+		return 0, nil
+	}
+	var n int
+	for _, ts := range tss {
+		if err := rw.Push(ts); err != nil {
+			return n, fmt.Errorf("remote write failure: %s", err)
+		}
+		n += len(ts.Samples)
+	}
+	return n, nil
+}
diff --git a/app/vmalert/rule/rule_test.go b/app/vmalert/rule/rule_test.go
new file mode 100644
index 000000000..45dbb2894
--- /dev/null
+++ b/app/vmalert/rule/rule_test.go
@@ -0,0 +1,81 @@
+package rule
+
+import (
+	"sync"
+	"testing"
+	"time"
+)
+
+func TestRule_state(t *testing.T) {
+	stateEntriesN := 20
+	r := &AlertingRule{state: &ruleState{entries: make([]StateEntry, stateEntriesN)}}
+	e := r.state.getLast()
+	if !e.At.IsZero() {
+		t.Fatalf("expected entry to be zero")
+	}
+
+	now := time.Now()
+	r.state.add(StateEntry{At: now})
+
+	e = r.state.getLast()
+	if e.At != now {
+		t.Fatalf("expected entry at %v to be equal to %v",
+			e.At, now)
+	}
+
+	time.Sleep(time.Millisecond)
+	now2 := time.Now()
+	r.state.add(StateEntry{At: now2})
+
+	e = r.state.getLast()
+	if e.At != now2 {
+		t.Fatalf("expected entry at %v to be equal to %v",
+			e.At, now2)
+	}
+
+	if len(r.state.getAll()) != 2 {
+		t.Fatalf("expected for state to have 2 entries only; got %d",
+			len(r.state.getAll()),
+		)
+	}
+
+	var last time.Time
+	for i := 0; i < stateEntriesN*2; i++ {
+		last = time.Now()
+		r.state.add(StateEntry{At: last})
+	}
+
+	e = r.state.getLast()
+	if e.At != last {
+		t.Fatalf("expected entry at %v to be equal to %v",
+			e.At, last)
+	}
+
+	if len(r.state.getAll()) != stateEntriesN {
+		t.Fatalf("expected for state to have %d entries only; got %d",
+			stateEntriesN, len(r.state.getAll()),
+		)
+	}
+}
+
+// TestRule_stateConcurrent supposed to test concurrent
+// execution of state updates.
+// Should be executed with -race flag
+func TestRule_stateConcurrent(_ *testing.T) {
+	r := &AlertingRule{state: &ruleState{entries: make([]StateEntry, 20)}}
+	const workers = 50
+	const iterations = 100
+	wg := sync.WaitGroup{}
+	wg.Add(workers)
+	for i := 0; i < workers; i++ {
+		go func() {
+			defer wg.Done()
+			for i := 0; i < iterations; i++ {
+				r.state.add(StateEntry{At: time.Now()})
+				r.state.getAll()
+				r.state.getLast()
+			}
+		}()
+	}
+	wg.Wait()
+}
diff --git a/app/vmalert/helpers_test.go b/app/vmalert/rule/test_helpers.go
similarity index 54%
rename from app/vmalert/helpers_test.go
rename to app/vmalert/rule/test_helpers.go
index 95e7c9f44..dcf23dc76 100644
--- a/app/vmalert/helpers_test.go
+++ b/app/vmalert/rule/test_helpers.go
@@ -1,239 +1,18 @@
-package main
+package rule
 
 import (
-	"context"
 	"fmt"
-	"net/http"
 	"reflect"
 	"sort"
-	"sync"
 	"testing"
-	"time"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 )
 
-type fakeQuerier struct {
-	sync.Mutex
-	metrics []datasource.Metric
-	err     error
-}
-
-func (fq *fakeQuerier) setErr(err error) {
-	fq.Lock()
-	fq.err = err
-	fq.Unlock()
-}
-
-func (fq *fakeQuerier) reset() {
-	fq.Lock()
-	fq.err = nil
-	fq.metrics = fq.metrics[:0]
-	fq.Unlock()
-}
-
-func (fq *fakeQuerier) add(metrics ...datasource.Metric) {
-	fq.Lock()
-	fq.metrics = append(fq.metrics, metrics...)
-	fq.Unlock()
-}
-
-func (fq *fakeQuerier) BuildWithParams(_ datasource.QuerierParams) datasource.Querier {
-	return fq
-}
-
-func (fq *fakeQuerier) QueryRange(ctx context.Context, q string, _, _ time.Time) (datasource.Result, error) {
-	req, _, err := fq.Query(ctx, q, time.Now())
-	return req, err
-}
-
-func (fq *fakeQuerier) Query(_ context.Context, _ string, _ time.Time) (datasource.Result, *http.Request, error) {
-	fq.Lock()
-	defer fq.Unlock()
-	if fq.err != nil {
-		return datasource.Result{}, nil, fq.err
-	}
-	cp := make([]datasource.Metric, len(fq.metrics))
-	copy(cp, fq.metrics)
-	req, _ := http.NewRequest(http.MethodPost, "foo.com", nil)
-	return datasource.Result{Data: cp}, req, nil
-}
-
-type fakeQuerierWithRegistry struct {
-	sync.Mutex
-	registry map[string][]datasource.Metric
-}
-
-func (fqr *fakeQuerierWithRegistry) set(key string, metrics ...datasource.Metric) {
-	fqr.Lock()
-	if fqr.registry == nil {
-		fqr.registry = make(map[string][]datasource.Metric)
-	}
-	fqr.registry[key] = metrics
-	fqr.Unlock()
-}
-
-func (fqr *fakeQuerierWithRegistry) reset() {
-	fqr.Lock()
-	fqr.registry = nil
-	fqr.Unlock()
-}
-
-func (fqr *fakeQuerierWithRegistry) BuildWithParams(_ datasource.QuerierParams) datasource.Querier {
-	return fqr
-}
-
-func (fqr *fakeQuerierWithRegistry) QueryRange(ctx context.Context, q string, _, _ time.Time) (datasource.Result, error) {
-	req, _, err := fqr.Query(ctx, q, time.Now())
-	return req, err
-}
-
-func (fqr *fakeQuerierWithRegistry) Query(_ context.Context, expr string, _ time.Time) (datasource.Result, *http.Request, error) {
-	fqr.Lock()
-	defer fqr.Unlock()
-
-	req, _ := http.NewRequest(http.MethodPost, "foo.com", nil)
-	metrics, ok := fqr.registry[expr]
-	if !ok {
-		return datasource.Result{}, req, nil
-	}
-	cp := make([]datasource.Metric, len(metrics))
-	copy(cp, metrics)
-	return datasource.Result{Data: cp}, req, nil
-}
-
-type fakeQuerierWithDelay struct {
-	fakeQuerier
-	delay time.Duration
-}
-
-func (fqd *fakeQuerierWithDelay) Query(ctx context.Context, expr string, ts time.Time) (datasource.Result, *http.Request, error) {
-	timer := time.NewTimer(fqd.delay)
-	select {
-	case <-ctx.Done():
-	case <-timer.C:
-	}
-	return fqd.fakeQuerier.Query(ctx, expr, ts)
-}
-
-func (fqd *fakeQuerierWithDelay) BuildWithParams(_ datasource.QuerierParams) datasource.Querier {
-	return fqd
-}
-
-type fakeNotifier struct {
-	sync.Mutex
-	alerts []notifier.Alert
-	// records number of received alerts in total
-	counter int
-}
-
-func (*fakeNotifier) Close()       {}
-func (*fakeNotifier) Addr() string { return "" }
-func (fn *fakeNotifier) Send(_ context.Context, alerts []notifier.Alert, _ map[string]string) error {
-	fn.Lock()
-	defer fn.Unlock()
-	fn.counter += len(alerts)
-	fn.alerts = alerts
-	return nil
-}
-
-func (fn *fakeNotifier) getCounter() int {
-	fn.Lock()
-	defer fn.Unlock()
-	return fn.counter
-}
-
-func (fn *fakeNotifier) getAlerts() []notifier.Alert {
-	fn.Lock()
-	defer fn.Unlock()
-	return fn.alerts
-}
-
-type faultyNotifier struct {
-	fakeNotifier
-}
-
-func (fn *faultyNotifier) Send(ctx context.Context, _ []notifier.Alert, _ map[string]string) error {
-	d, ok := ctx.Deadline()
-	if ok {
-		time.Sleep(time.Until(d))
-	}
-	return fmt.Errorf("send failed")
-}
-
-func metricWithValueAndLabels(t *testing.T, value float64, labels ...string) datasource.Metric {
-	return metricWithValuesAndLabels(t, []float64{value}, labels...)
-}
-
-func metricWithValuesAndLabels(t *testing.T, values []float64, labels ...string) datasource.Metric {
-	t.Helper()
-	m := metricWithLabels(t, labels...)
-	m.Values = values
-	for i := range values {
-		m.Timestamps = append(m.Timestamps, int64(i))
-	}
-	return m
-}
-
-func metricWithLabels(t *testing.T, labels ...string) datasource.Metric {
-	t.Helper()
-	if len(labels) == 0 || len(labels)%2 != 0 {
-		t.Fatalf("expected to get even number of labels")
-	}
-	m := datasource.Metric{Values: []float64{1}, Timestamps: []int64{1}}
-	for i := 0; i < len(labels); i += 2 {
-		m.Labels = append(m.Labels, datasource.Label{
-			Name:  labels[i],
-			Value: labels[i+1],
-		})
-	}
-	return m
-}
-
-func toPromLabels(t *testing.T, labels ...string) []prompbmarshal.Label {
-	t.Helper()
-	if len(labels) == 0 || len(labels)%2 != 0 {
-		t.Fatalf("expected to get even number of labels")
-	}
-	var ls []prompbmarshal.Label
-	for i := 0; i < len(labels); i += 2 {
-		ls = append(ls, prompbmarshal.Label{
-			Name:  labels[i],
-			Value: labels[i+1],
-		})
-	}
-	return ls
-}
-
-func compareGroups(t *testing.T, a, b *Group) {
-	t.Helper()
-	if a.Name != b.Name {
-		t.Fatalf("expected group name %q; got %q", a.Name, b.Name)
-	}
-	if a.File != b.File {
-		t.Fatalf("expected group %q file name %q; got %q", a.Name, a.File, b.File)
-	}
-	if a.Interval != b.Interval {
-		t.Fatalf("expected group %q interval %v; got %v", a.Name, a.Interval, b.Interval)
-	}
-	if len(a.Rules) != len(b.Rules) {
-		t.Fatalf("expected group %s to have %d rules; got: %d",
-			a.Name, len(a.Rules), len(b.Rules))
-	}
-	for i, r := range a.Rules {
-		got, want := r, b.Rules[i]
-		if a.ID() != b.ID() {
-			t.Fatalf("expected to have rule %q; got %q", want.ID(), got.ID())
-		}
-		if err := compareRules(t, want, got); err != nil {
-			t.Fatalf("comparison error: %s", err)
-		}
-	}
-}
-
-func compareRules(t *testing.T, a, b Rule) error {
+// CompareRules is a test helper func for other tests
+func CompareRules(t *testing.T, a, b Rule) error {
 	t.Helper()
 	switch v := a.(type) {
 	case *AlertingRule:
@@ -287,6 +66,50 @@ func compareAlertingRules(t *testing.T, a, b *AlertingRule) error {
 	return nil
 }
 
+func metricWithValueAndLabels(t *testing.T, value float64, labels ...string) datasource.Metric {
+	return metricWithValuesAndLabels(t, []float64{value}, labels...)
+}
+
+func metricWithValuesAndLabels(t *testing.T, values []float64, labels ...string) datasource.Metric {
+	t.Helper()
+	m := metricWithLabels(t, labels...)
+	m.Values = values
+	for i := range values {
+		m.Timestamps = append(m.Timestamps, int64(i))
+	}
+	return m
+}
+
+func metricWithLabels(t *testing.T, labels ...string) datasource.Metric {
+	t.Helper()
+	if len(labels) == 0 || len(labels)%2 != 0 {
+		t.Fatalf("expected to get even number of labels")
+	}
+	m := datasource.Metric{Values: []float64{1}, Timestamps: []int64{1}}
+	for i := 0; i < len(labels); i += 2 {
+		m.Labels = append(m.Labels, datasource.Label{
+			Name:  labels[i],
+			Value: labels[i+1],
+		})
+	}
+	return m
+}
+
+func toPromLabels(t *testing.T, labels ...string) []prompbmarshal.Label {
+	t.Helper()
+	if len(labels) == 0 || len(labels)%2 != 0 {
+		t.Fatalf("expected to get even number of labels")
+	}
+	var ls []prompbmarshal.Label
+	for i := 0; i < len(labels); i += 2 {
+		ls = append(ls, prompbmarshal.Label{
+			Name:  labels[i],
+			Value: labels[i+1],
+		})
+	}
+	return ls
+}
+
 func compareTimeSeries(t *testing.T, a, b []prompbmarshal.TimeSeries) error {
 	t.Helper()
 	if len(a) != len(b) {
diff --git a/app/vmalert/utils.go b/app/vmalert/rule/utils.go
similarity index 99%
rename from app/vmalert/utils.go
rename to app/vmalert/rule/utils.go
index d5c729825..2e435861b 100644
--- a/app/vmalert/utils.go
+++ b/app/vmalert/rule/utils.go
@@ -1,4 +1,4 @@
-package main
+package rule
 
 import (
 	"fmt"
diff --git a/app/vmalert/utils_test.go b/app/vmalert/rule/utils_test.go
similarity index 99%
rename from app/vmalert/utils_test.go
rename to app/vmalert/rule/utils_test.go
index 5bee17ca6..e87cff599 100644
--- a/app/vmalert/utils_test.go
+++ b/app/vmalert/rule/utils_test.go
@@ -1,4 +1,4 @@
-package main
+package rule
 
 import (
 	"net/http"
diff --git a/app/vmalert/rule_test.go b/app/vmalert/rule_test.go
deleted file mode 100644
index 1c5c61451..000000000
--- a/app/vmalert/rule_test.go
+++ /dev/null
@@ -1,100 +0,0 @@
-package main
-
-import (
-	"sync"
-	"testing"
-	"time"
-)
-
-func TestRule_stateDisabled(t *testing.T) {
-	state := newRuleState(-1)
-	e := state.getLast()
-	if !e.at.IsZero() {
-		t.Fatalf("expected entry to be zero")
-	}
-
-	state.add(ruleStateEntry{at: time.Now()})
-	state.add(ruleStateEntry{at: time.Now()})
-	state.add(ruleStateEntry{at: time.Now()})
-
-	if len(state.getAll()) != 1 {
-		// state should store at least one update at any circumstances
-		t.Fatalf("expected for state to have %d entries; got %d",
-			1, len(state.getAll()),
-		)
-	}
-}
-func TestRule_state(t *testing.T) {
-	stateEntriesN := 20
-	state := newRuleState(stateEntriesN)
-	e := state.getLast()
-	if !e.at.IsZero() {
-		t.Fatalf("expected entry to be zero")
-	}
-
-	now := time.Now()
-	state.add(ruleStateEntry{at: now})
-
-	e = state.getLast()
-	if e.at != now {
-		t.Fatalf("expected entry at %v to be equal to %v",
-			e.at, now)
-	}
-
-	time.Sleep(time.Millisecond)
-	now2 := time.Now()
-	state.add(ruleStateEntry{at: now2})
-
-	e = state.getLast()
-	if e.at != now2 {
-		t.Fatalf("expected entry at %v to be equal to %v",
-			e.at, now2)
-	}
-
-	if len(state.getAll()) != 2 {
-		t.Fatalf("expected for state to have 2 entries only; got %d",
-			len(state.getAll()),
-		)
-	}
-
-	var last time.Time
-	for i := 0; i < stateEntriesN*2; i++ {
-		last = time.Now()
-		state.add(ruleStateEntry{at: last})
-	}
-
-	e = state.getLast()
-	if e.at != last {
-		t.Fatalf("expected entry at %v to be equal to %v",
-			e.at, last)
-	}
-
-	if len(state.getAll()) != stateEntriesN {
-		t.Fatalf("expected for state to have %d entries only; got %d",
-			stateEntriesN, len(state.getAll()),
-		)
-	}
-}
-
-// TestRule_stateConcurrent supposed to test concurrent
-// execution of state updates.
-// Should be executed with -race flag
-func TestRule_stateConcurrent(_ *testing.T) {
-	state := newRuleState(20)
-
-	const workers = 50
-	const iterations = 100
-	wg := sync.WaitGroup{}
-	wg.Add(workers)
-	for i := 0; i < workers; i++ {
-		go func() {
-			defer wg.Done()
-			for i := 0; i < iterations; i++ {
-				state.add(ruleStateEntry{at: time.Now()})
-				state.getAll()
-				state.getLast()
-			}
-		}()
-	}
-	wg.Wait()
-}
diff --git a/app/vmalert/web.go b/app/vmalert/web.go
index 3d91fb6aa..b93ebc067 100644
--- a/app/vmalert/web.go
+++ b/app/vmalert/web.go
@@ -10,6 +10,7 @@ import (
 	"strings"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/tpl"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
@@ -143,38 +144,32 @@ func (rh *requestHandler) handler(w http.ResponseWriter, r *http.Request) bool {
 	}
 }
 
-const (
-	paramGroupID = "group_id"
-	paramAlertID = "alert_id"
-	paramRuleID  = "rule_id"
-)
-
-func (rh *requestHandler) getRule(r *http.Request) (APIRule, error) {
-	groupID, err := strconv.ParseUint(r.FormValue(paramGroupID), 10, 0)
+func (rh *requestHandler) getRule(r *http.Request) (apiRule, error) {
+	groupID, err := strconv.ParseUint(r.FormValue(paramGroupID), 10, 64)
 	if err != nil {
-		return APIRule{}, fmt.Errorf("failed to read %q param: %s", paramGroupID, err)
+		return apiRule{}, fmt.Errorf("failed to read %q param: %s", paramGroupID, err)
 	}
-	ruleID, err := strconv.ParseUint(r.FormValue(paramRuleID), 10, 0)
+	ruleID, err := strconv.ParseUint(r.FormValue(paramRuleID), 10, 64)
 	if err != nil {
-		return APIRule{}, fmt.Errorf("failed to read %q param: %s", paramRuleID, err)
+		return apiRule{}, fmt.Errorf("failed to read %q param: %s", paramRuleID, err)
 	}
-	rule, err := rh.m.RuleAPI(groupID, ruleID)
+	obj, err := rh.m.ruleAPI(groupID, ruleID)
 	if err != nil {
-		return APIRule{}, errResponse(err, http.StatusNotFound)
+		return apiRule{}, errResponse(err, http.StatusNotFound)
 	}
-	return rule, nil
+	return obj, nil
 }
 
-func (rh *requestHandler) getAlert(r *http.Request) (*APIAlert, error) {
-	groupID, err := strconv.ParseUint(r.FormValue(paramGroupID), 10, 0)
+func (rh *requestHandler) getAlert(r *http.Request) (*apiAlert, error) {
+	groupID, err := strconv.ParseUint(r.FormValue(paramGroupID), 10, 64)
 	if err != nil {
 		return nil, fmt.Errorf("failed to read %q param: %s", paramGroupID, err)
 	}
-	alertID, err := strconv.ParseUint(r.FormValue(paramAlertID), 10, 0)
+	alertID, err := strconv.ParseUint(r.FormValue(paramAlertID), 10, 64)
 	if err != nil {
 		return nil, fmt.Errorf("failed to read %q param: %s", paramAlertID, err)
 	}
-	a, err := rh.m.AlertAPI(groupID, alertID)
+	a, err := rh.m.alertAPI(groupID, alertID)
 	if err != nil {
 		return nil, errResponse(err, http.StatusNotFound)
 	}
@@ -184,17 +179,17 @@ func (rh *requestHandler) getAlert(r *http.Request) (*APIAlert, error) {
 type listGroupsResponse struct {
 	Status string `json:"status"`
 	Data   struct {
-		Groups []APIGroup `json:"groups"`
+		Groups []apiGroup `json:"groups"`
 	} `json:"data"`
 }
 
-func (rh *requestHandler) groups() []APIGroup {
+func (rh *requestHandler) groups() []apiGroup {
 	rh.m.groupsMu.RLock()
 	defer rh.m.groupsMu.RUnlock()
 
-	groups := make([]APIGroup, 0)
+	groups := make([]apiGroup, 0)
 	for _, g := range rh.m.groups {
-		groups = append(groups, g.toAPI())
+		groups = append(groups, groupToAPI(g))
 	}
 
 	// sort list of alerts for deterministic output
@@ -221,35 +216,35 @@ func (rh *requestHandler) listGroups() ([]byte, error) {
 type listAlertsResponse struct {
 	Status string `json:"status"`
 	Data   struct {
-		Alerts []*APIAlert `json:"alerts"`
+		Alerts []*apiAlert `json:"alerts"`
 	} `json:"data"`
 }
 
-func (rh *requestHandler) groupAlerts() []GroupAlerts {
+func (rh *requestHandler) groupAlerts() []groupAlerts {
 	rh.m.groupsMu.RLock()
 	defer rh.m.groupsMu.RUnlock()
 
-	var groupAlerts []GroupAlerts
+	var gAlerts []groupAlerts
 	for _, g := range rh.m.groups {
-		var alerts []*APIAlert
+		var alerts []*apiAlert
 		for _, r := range g.Rules {
-			a, ok := r.(*AlertingRule)
+			a, ok := r.(*rule.AlertingRule)
 			if !ok {
 				continue
 			}
-			alerts = append(alerts, a.AlertsToAPI()...)
+			alerts = append(alerts, ruleToAPIAlert(a)...)
 		}
 		if len(alerts) > 0 {
-			groupAlerts = append(groupAlerts, GroupAlerts{
-				Group:  g.toAPI(),
+			gAlerts = append(gAlerts, groupAlerts{
+				Group:  groupToAPI(g),
 				Alerts: alerts,
 			})
 		}
 	}
-	sort.Slice(groupAlerts, func(i, j int) bool {
-		return groupAlerts[i].Group.Name < groupAlerts[j].Group.Name
+	sort.Slice(gAlerts, func(i, j int) bool {
+		return gAlerts[i].Group.Name < gAlerts[j].Group.Name
 	})
-	return groupAlerts
+	return gAlerts
 }
 
 func (rh *requestHandler) listAlerts() ([]byte, error) {
@@ -257,14 +252,14 @@ func (rh *requestHandler) listAlerts() ([]byte, error) {
 	defer rh.m.groupsMu.RUnlock()
 
 	lr := listAlertsResponse{Status: "success"}
-	lr.Data.Alerts = make([]*APIAlert, 0)
+	lr.Data.Alerts = make([]*apiAlert, 0)
 	for _, g := range rh.m.groups {
 		for _, r := range g.Rules {
-			a, ok := r.(*AlertingRule)
+			a, ok := r.(*rule.AlertingRule)
 			if !ok {
 				continue
 			}
-			lr.Data.Alerts = append(lr.Data.Alerts, a.AlertsToAPI()...)
+			lr.Data.Alerts = append(lr.Data.Alerts, ruleToAPIAlert(a)...)
 		}
 	}
 
diff --git a/app/vmalert/web.qtpl b/app/vmalert/web.qtpl
index 425ea6ea5..6186319e0 100644
--- a/app/vmalert/web.qtpl
+++ b/app/vmalert/web.qtpl
@@ -38,7 +38,7 @@ btn-primary
     {% endif %}
 {% endfunc %}
 
-{% func ListGroups(r *http.Request, originGroups []APIGroup) %}
+{% func ListGroups(r *http.Request, originGroups []apiGroup) %}
     {%code prefix := utils.Prefix(r.URL.Path) %}
     {%= tpl.Header(r, navItems, "Groups", getLastConfigError()) %}
         {%code
@@ -46,9 +46,9 @@ btn-primary
             rOk := make(map[string]int)
             rNotOk := make(map[string]int)
             rNoMatch := make(map[string]int)
-            var groups []APIGroup
+            var groups []apiGroup
             for _, g := range originGroups {
-                var rules []APIRule
+                var rules []apiRule
                 for _, r := range g.Rules {
                     if r.LastError != "" {
                         rNotOk[g.ID]++
@@ -166,7 +166,7 @@ btn-primary
 {% endfunc %}
 
 
-{% func ListAlerts(r *http.Request, groupAlerts []GroupAlerts) %}
+{% func ListAlerts(r *http.Request, groupAlerts []groupAlerts) %}
     {%code prefix := utils.Prefix(r.URL.Path) %}
     {%= tpl.Header(r, navItems, "Alerts", getLastConfigError()) %}
     {% if len(groupAlerts) > 0 %}
@@ -183,7 +183,7 @@ btn-primary
             </div>
             {%code
                 var keys []string
-                alertsByRule := make(map[string][]*APIAlert)
+                alertsByRule := make(map[string][]*apiAlert)
                 for _, alert := range ga.Alerts {
                     if len(alertsByRule[alert.RuleID]) < 1 {
                         keys = append(keys, alert.RuleID)
@@ -310,7 +310,7 @@ btn-primary
 
 {% endfunc %}
 
-{% func Alert(r *http.Request, alert *APIAlert) %}
+{% func Alert(r *http.Request, alert *apiAlert) %}
     {%code prefix := utils.Prefix(r.URL.Path) %}
     {%= tpl.Header(r, navItems, "", getLastConfigError()) %}
     {%code
@@ -397,7 +397,7 @@ btn-primary
 {% endfunc %}
 
 
-{% func RuleDetails(r *http.Request, rule APIRule) %}
+{% func RuleDetails(r *http.Request, rule apiRule) %}
     {%code prefix := utils.Prefix(r.URL.Path) %}
     {%= tpl.Header(r, navItems, "", getLastConfigError()) %}
     {%code
@@ -416,9 +416,9 @@ btn-primary
         var seriesFetchedEnabled bool
         var seriesFetchedWarning bool
         for _, u := range rule.Updates {
-          if u.seriesFetched != nil {
+          if u.SeriesFetched != nil {
             seriesFetchedEnabled = true
-            if *u.seriesFetched == 0 && u.samples == 0{
+            if *u.SeriesFetched == 0 && u.Samples == 0{
                 seriesFetchedWarning = true
             }
           }
@@ -537,23 +537,23 @@ btn-primary
             <tbody>
 
      {% for _, u := range rule.Updates %}
-             <tr{% if u.err != nil %} class="alert-danger"{% endif %}>
+             <tr{% if u.Err != nil %} class="alert-danger"{% endif %}>
                  <td>
-                    <span class="badge bg-primary rounded-pill me-3" title="Updated at">{%s u.time.Format(time.RFC3339) %}</span>
+                    <span class="badge bg-primary rounded-pill me-3" title="Updated at">{%s u.Time.Format(time.RFC3339) %}</span>
                  </td>
-                 <td class="text-center">{%d u.samples %}</td>
-                 {% if seriesFetchedEnabled %}<td class="text-center">{% if u.seriesFetched != nil %}{%d *u.seriesFetched %}{% endif %}</td>{% endif %}
-                 <td class="text-center">{%f.3 u.duration.Seconds() %}s</td>
-                 <td class="text-center">{%s u.at.Format(time.RFC3339) %}</td>
+                 <td class="text-center">{%d u.Samples %}</td>
+                 {% if seriesFetchedEnabled %}<td class="text-center">{% if u.SeriesFetched != nil %}{%d *u.SeriesFetched %}{% endif %}</td>{% endif %}
+                 <td class="text-center">{%f.3 u.Duration.Seconds() %}s</td>
+                 <td class="text-center">{%s u.At.Format(time.RFC3339) %}</td>
                  <td>
-                    <textarea class="curl-area" rows="1" onclick="this.focus();this.select()">{%s u.curl %}</textarea>
+                    <textarea class="curl-area" rows="1" onclick="this.focus();this.select()">{%s u.Curl %}</textarea>
                 </td>
              </tr>
           </li>
-          {% if u.err != nil %}
-             <tr{% if u.err != nil %} class="alert-danger"{% endif %}>
+          {% if u.Err != nil %}
+             <tr{% if u.Err != nil %} class="alert-danger"{% endif %}>
                <td colspan="{% if seriesFetchedEnabled %}6{%else%}5{%endif%}">
-                   <span class="alert-danger">{%v u.err %}</span>
+                   <span class="alert-danger">{%v u.Err %}</span>
                </td>
              </tr>
           {% endif %}
@@ -582,7 +582,7 @@ btn-primary
 <span class="badge bg-warning text-dark" title="This firing state is kept because of `keep_firing_for`">stabilizing</span>
 {% endfunc %}
 
-{% func seriesFetchedWarn(r APIRule) %}
+{% func seriesFetchedWarn(r apiRule) %}
 {% if isNoMatch(r) %}
 <svg xmlns="http://www.w3.org/2000/svg"
     data-bs-toggle="tooltip"
@@ -596,7 +596,7 @@ btn-primary
 {% endfunc %}
 
 {%code
-  func isNoMatch (r APIRule) bool {
+  func isNoMatch (r apiRule) bool {
     return r.LastSamples == 0 && r.LastSeriesFetched != nil && *r.LastSeriesFetched == 0
   }
 %}
diff --git a/app/vmalert/web.qtpl.go b/app/vmalert/web.qtpl.go
index bb95cc89b..6a656c0d7 100644
--- a/app/vmalert/web.qtpl.go
+++ b/app/vmalert/web.qtpl.go
@@ -196,7 +196,7 @@ func buttonActive(filter, expValue string) string {
 }
 
 //line app/vmalert/web.qtpl:41
-func StreamListGroups(qw422016 *qt422016.Writer, r *http.Request, originGroups []APIGroup) {
+func StreamListGroups(qw422016 *qt422016.Writer, r *http.Request, originGroups []apiGroup) {
 //line app/vmalert/web.qtpl:41
 	qw422016.N().S(`
     `)
@@ -216,9 +216,9 @@ func StreamListGroups(qw422016 *qt422016.Writer, r *http.Request, originGroups [
 	rOk := make(map[string]int)
 	rNotOk := make(map[string]int)
 	rNoMatch := make(map[string]int)
-	var groups []APIGroup
+	var groups []apiGroup
 	for _, g := range originGroups {
-		var rules []APIRule
+		var rules []apiRule
 		for _, r := range g.Rules {
 			if r.LastError != "" {
 				rNotOk[g.ID]++
@@ -610,7 +610,7 @@ func StreamListGroups(qw422016 *qt422016.Writer, r *http.Request, originGroups [
 }
 
 //line app/vmalert/web.qtpl:166
-func WriteListGroups(qq422016 qtio422016.Writer, r *http.Request, originGroups []APIGroup) {
+func WriteListGroups(qq422016 qtio422016.Writer, r *http.Request, originGroups []apiGroup) {
 //line app/vmalert/web.qtpl:166
 	qw422016 := qt422016.AcquireWriter(qq422016)
 //line app/vmalert/web.qtpl:166
@@ -621,7 +621,7 @@ func WriteListGroups(qq422016 qtio422016.Writer, r *http.Request, originGroups [
 }
 
 //line app/vmalert/web.qtpl:166
-func ListGroups(r *http.Request, originGroups []APIGroup) string {
+func ListGroups(r *http.Request, originGroups []apiGroup) string {
 //line app/vmalert/web.qtpl:166
 	qb422016 := qt422016.AcquireByteBuffer()
 //line app/vmalert/web.qtpl:166
@@ -636,7 +636,7 @@ func ListGroups(r *http.Request, originGroups []APIGroup) string {
 }
 
 //line app/vmalert/web.qtpl:169
-func StreamListAlerts(qw422016 *qt422016.Writer, r *http.Request, groupAlerts []GroupAlerts) {
+func StreamListAlerts(qw422016 *qt422016.Writer, r *http.Request, groupAlerts []groupAlerts) {
 //line app/vmalert/web.qtpl:169
 	qw422016.N().S(`
     `)
@@ -712,7 +712,7 @@ func StreamListAlerts(qw422016 *qt422016.Writer, r *http.Request, groupAlerts []
             `)
 //line app/vmalert/web.qtpl:185
 			var keys []string
-			alertsByRule := make(map[string][]*APIAlert)
+			alertsByRule := make(map[string][]*apiAlert)
 			for _, alert := range ga.Alerts {
 				if len(alertsByRule[alert.RuleID]) < 1 {
 					keys = append(keys, alert.RuleID)
@@ -891,7 +891,7 @@ func StreamListAlerts(qw422016 *qt422016.Writer, r *http.Request, groupAlerts []
 }
 
 //line app/vmalert/web.qtpl:255
-func WriteListAlerts(qq422016 qtio422016.Writer, r *http.Request, groupAlerts []GroupAlerts) {
+func WriteListAlerts(qq422016 qtio422016.Writer, r *http.Request, groupAlerts []groupAlerts) {
 //line app/vmalert/web.qtpl:255
 	qw422016 := qt422016.AcquireWriter(qq422016)
 //line app/vmalert/web.qtpl:255
@@ -902,7 +902,7 @@ func WriteListAlerts(qq422016 qtio422016.Writer, r *http.Request, groupAlerts []
 }
 
 //line app/vmalert/web.qtpl:255
-func ListAlerts(r *http.Request, groupAlerts []GroupAlerts) string {
+func ListAlerts(r *http.Request, groupAlerts []groupAlerts) string {
 //line app/vmalert/web.qtpl:255
 	qb422016 := qt422016.AcquireByteBuffer()
 //line app/vmalert/web.qtpl:255
@@ -1091,7 +1091,7 @@ func ListTargets(r *http.Request, targets map[notifier.TargetType][]notifier.Tar
 }
 
 //line app/vmalert/web.qtpl:313
-func StreamAlert(qw422016 *qt422016.Writer, r *http.Request, alert *APIAlert) {
+func StreamAlert(qw422016 *qt422016.Writer, r *http.Request, alert *apiAlert) {
 //line app/vmalert/web.qtpl:313
 	qw422016.N().S(`
     `)
@@ -1274,7 +1274,7 @@ func StreamAlert(qw422016 *qt422016.Writer, r *http.Request, alert *APIAlert) {
 }
 
 //line app/vmalert/web.qtpl:397
-func WriteAlert(qq422016 qtio422016.Writer, r *http.Request, alert *APIAlert) {
+func WriteAlert(qq422016 qtio422016.Writer, r *http.Request, alert *apiAlert) {
 //line app/vmalert/web.qtpl:397
 	qw422016 := qt422016.AcquireWriter(qq422016)
 //line app/vmalert/web.qtpl:397
@@ -1285,7 +1285,7 @@ func WriteAlert(qq422016 qtio422016.Writer, r *http.Request, alert *APIAlert) {
 }
 
 //line app/vmalert/web.qtpl:397
-func Alert(r *http.Request, alert *APIAlert) string {
+func Alert(r *http.Request, alert *apiAlert) string {
 //line app/vmalert/web.qtpl:397
 	qb422016 := qt422016.AcquireByteBuffer()
 //line app/vmalert/web.qtpl:397
@@ -1300,7 +1300,7 @@ func Alert(r *http.Request, alert *APIAlert) string {
 }
 
 //line app/vmalert/web.qtpl:400
-func StreamRuleDetails(qw422016 *qt422016.Writer, r *http.Request, rule APIRule) {
+func StreamRuleDetails(qw422016 *qt422016.Writer, r *http.Request, rule apiRule) {
 //line app/vmalert/web.qtpl:400
 	qw422016.N().S(`
     `)
@@ -1331,9 +1331,9 @@ func StreamRuleDetails(qw422016 *qt422016.Writer, r *http.Request, rule APIRule)
 	var seriesFetchedEnabled bool
 	var seriesFetchedWarning bool
 	for _, u := range rule.Updates {
-		if u.seriesFetched != nil {
+		if u.SeriesFetched != nil {
 			seriesFetchedEnabled = true
-			if *u.seriesFetched == 0 && u.samples == 0 {
+			if *u.SeriesFetched == 0 && u.Samples == 0 {
 				seriesFetchedWarning = true
 			}
 		}
@@ -1587,7 +1587,7 @@ func StreamRuleDetails(qw422016 *qt422016.Writer, r *http.Request, rule APIRule)
 		qw422016.N().S(`
              <tr`)
 //line app/vmalert/web.qtpl:540
-		if u.err != nil {
+		if u.Err != nil {
 //line app/vmalert/web.qtpl:540
 			qw422016.N().S(` class="alert-danger"`)
 //line app/vmalert/web.qtpl:540
@@ -1597,13 +1597,13 @@ func StreamRuleDetails(qw422016 *qt422016.Writer, r *http.Request, rule APIRule)
                  <td>
                     <span class="badge bg-primary rounded-pill me-3" title="Updated at">`)
 //line app/vmalert/web.qtpl:542
-		qw422016.E().S(u.time.Format(time.RFC3339))
+		qw422016.E().S(u.Time.Format(time.RFC3339))
 //line app/vmalert/web.qtpl:542
 		qw422016.N().S(`</span>
                  </td>
                  <td class="text-center">`)
 //line app/vmalert/web.qtpl:544
-		qw422016.N().D(u.samples)
+		qw422016.N().D(u.Samples)
 //line app/vmalert/web.qtpl:544
 		qw422016.N().S(`</td>
                  `)
@@ -1612,9 +1612,9 @@ func StreamRuleDetails(qw422016 *qt422016.Writer, r *http.Request, rule APIRule)
 //line app/vmalert/web.qtpl:545
 			qw422016.N().S(`<td class="text-center">`)
 //line app/vmalert/web.qtpl:545
-			if u.seriesFetched != nil {
+			if u.SeriesFetched != nil {
 //line app/vmalert/web.qtpl:545
-				qw422016.N().D(*u.seriesFetched)
+				qw422016.N().D(*u.SeriesFetched)
 //line app/vmalert/web.qtpl:545
 			}
 //line app/vmalert/web.qtpl:545
@@ -1625,18 +1625,18 @@ func StreamRuleDetails(qw422016 *qt422016.Writer, r *http.Request, rule APIRule)
 		qw422016.N().S(`
                  <td class="text-center">`)
 //line app/vmalert/web.qtpl:546
-		qw422016.N().FPrec(u.duration.Seconds(), 3)
+		qw422016.N().FPrec(u.Duration.Seconds(), 3)
 //line app/vmalert/web.qtpl:546
 		qw422016.N().S(`s</td>
                  <td class="text-center">`)
 //line app/vmalert/web.qtpl:547
-		qw422016.E().S(u.at.Format(time.RFC3339))
+		qw422016.E().S(u.At.Format(time.RFC3339))
 //line app/vmalert/web.qtpl:547
 		qw422016.N().S(`</td>
                  <td>
                     <textarea class="curl-area" rows="1" onclick="this.focus();this.select()">`)
 //line app/vmalert/web.qtpl:549
-		qw422016.E().S(u.curl)
+		qw422016.E().S(u.Curl)
 //line app/vmalert/web.qtpl:549
 		qw422016.N().S(`</textarea>
                 </td>
@@ -1644,12 +1644,12 @@ func StreamRuleDetails(qw422016 *qt422016.Writer, r *http.Request, rule APIRule)
           </li>
           `)
 //line app/vmalert/web.qtpl:553
-		if u.err != nil {
+		if u.Err != nil {
 //line app/vmalert/web.qtpl:553
 			qw422016.N().S(`
              <tr`)
 //line app/vmalert/web.qtpl:554
-			if u.err != nil {
+			if u.Err != nil {
 //line app/vmalert/web.qtpl:554
 				qw422016.N().S(` class="alert-danger"`)
 //line app/vmalert/web.qtpl:554
@@ -1671,7 +1671,7 @@ func StreamRuleDetails(qw422016 *qt422016.Writer, r *http.Request, rule APIRule)
 			qw422016.N().S(`">
                    <span class="alert-danger">`)
 //line app/vmalert/web.qtpl:556
-			qw422016.E().V(u.err)
+			qw422016.E().V(u.Err)
 //line app/vmalert/web.qtpl:556
 			qw422016.N().S(`</span>
                </td>
@@ -1697,7 +1697,7 @@ func StreamRuleDetails(qw422016 *qt422016.Writer, r *http.Request, rule APIRule)
 }
 
 //line app/vmalert/web.qtpl:563
-func WriteRuleDetails(qq422016 qtio422016.Writer, r *http.Request, rule APIRule) {
+func WriteRuleDetails(qq422016 qtio422016.Writer, r *http.Request, rule apiRule) {
 //line app/vmalert/web.qtpl:563
 	qw422016 := qt422016.AcquireWriter(qq422016)
 //line app/vmalert/web.qtpl:563
@@ -1708,7 +1708,7 @@ func WriteRuleDetails(qq422016 qtio422016.Writer, r *http.Request, rule APIRule)
 }
 
 //line app/vmalert/web.qtpl:563
-func RuleDetails(r *http.Request, rule APIRule) string {
+func RuleDetails(r *http.Request, rule apiRule) string {
 //line app/vmalert/web.qtpl:563
 	qb422016 := qt422016.AcquireByteBuffer()
 //line app/vmalert/web.qtpl:563
@@ -1853,7 +1853,7 @@ func badgeStabilizing() string {
 }
 
 //line app/vmalert/web.qtpl:585
-func streamseriesFetchedWarn(qw422016 *qt422016.Writer, r APIRule) {
+func streamseriesFetchedWarn(qw422016 *qt422016.Writer, r apiRule) {
 //line app/vmalert/web.qtpl:585
 	qw422016.N().S(`
 `)
@@ -1879,7 +1879,7 @@ func streamseriesFetchedWarn(qw422016 *qt422016.Writer, r APIRule) {
 }
 
 //line app/vmalert/web.qtpl:596
-func writeseriesFetchedWarn(qq422016 qtio422016.Writer, r APIRule) {
+func writeseriesFetchedWarn(qq422016 qtio422016.Writer, r apiRule) {
 //line app/vmalert/web.qtpl:596
 	qw422016 := qt422016.AcquireWriter(qq422016)
 //line app/vmalert/web.qtpl:596
@@ -1890,7 +1890,7 @@ func writeseriesFetchedWarn(qq422016 qtio422016.Writer, r APIRule) {
 }
 
 //line app/vmalert/web.qtpl:596
-func seriesFetchedWarn(r APIRule) string {
+func seriesFetchedWarn(r apiRule) string {
 //line app/vmalert/web.qtpl:596
 	qb422016 := qt422016.AcquireByteBuffer()
 //line app/vmalert/web.qtpl:596
@@ -1905,6 +1905,6 @@ func seriesFetchedWarn(r APIRule) string {
 }
 
 //line app/vmalert/web.qtpl:599
-func isNoMatch(r APIRule) bool {
+func isNoMatch(r apiRule) bool {
 	return r.LastSamples == 0 && r.LastSeriesFetched != nil && *r.LastSeriesFetched == 0
 }
diff --git a/app/vmalert/web_test.go b/app/vmalert/web_test.go
index 951e92e96..c55ef5cbc 100644
--- a/app/vmalert/web_test.go
+++ b/app/vmalert/web_test.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"net/http"
@@ -9,32 +10,29 @@ import (
 	"testing"
 	"time"
 
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
 )
 
 func TestHandler(t *testing.T) {
-	ar := &AlertingRule{
-		Name: "alert",
-		alerts: map[uint64]*notifier.Alert{
-			0: {State: notifier.StateFiring},
-		},
-		state: newRuleState(10),
-	}
-	ar.state.add(ruleStateEntry{
-		time:    time.Now(),
-		at:      time.Now(),
-		samples: 10,
+	fq := &datasource.FakeQuerier{}
+	fq.Add(datasource.Metric{
+		Values: []float64{1}, Timestamps: []int64{0},
 	})
-	rr := &RecordingRule{
-		Name:  "record",
-		state: newRuleState(10),
+	g := &rule.Group{
+		Name:        "group",
+		Concurrency: 1,
 	}
-	g := &Group{
-		Name:  "group",
-		Rules: []Rule{ar, rr},
-	}
-	m := &manager{groups: make(map[uint64]*Group)}
-	m.groups[0] = g
+	ar := rule.NewAlertingRule(fq, g, config.Rule{ID: 0, Alert: "alert"})
+	rr := rule.NewRecordingRule(fq, g, config.Rule{ID: 1, Record: "record"})
+	g.Rules = []rule.Rule{ar, rr}
+	g.ExecOnce(context.Background(), func() []notifier.Notifier { return nil }, nil, time.Time{})
+
+	m := &manager{groups: map[uint64]*rule.Group{
+		g.ID(): g,
+	}}
 	rh := &requestHandler{m: m}
 
 	getResp := func(url string, to interface{}, code int) {
@@ -70,13 +68,13 @@ func TestHandler(t *testing.T) {
 	})
 
 	t.Run("/vmalert/rule", func(t *testing.T) {
-		a := ar.ToAPI()
+		a := ruleToAPI(ar)
 		getResp(ts.URL+"/vmalert/"+a.WebLink(), nil, 200)
-		r := rr.ToAPI()
+		r := ruleToAPI(rr)
 		getResp(ts.URL+"/vmalert/"+r.WebLink(), nil, 200)
 	})
 	t.Run("/vmalert/alert", func(t *testing.T) {
-		alerts := ar.AlertsToAPI()
+		alerts := ruleToAPIAlert(ar)
 		for _, a := range alerts {
 			getResp(ts.URL+"/vmalert/"+a.WebLink(), nil, 200)
 		}
@@ -103,14 +101,14 @@ func TestHandler(t *testing.T) {
 		}
 	})
 	t.Run("/api/v1/alert?alertID&groupID", func(t *testing.T) {
-		expAlert := ar.newAlertAPI(*ar.alerts[0])
-		alert := &APIAlert{}
+		expAlert := newAlertAPI(ar, ar.GetAlerts()[0])
+		alert := &apiAlert{}
 		getResp(ts.URL+"/"+expAlert.APILink(), alert, 200)
 		if !reflect.DeepEqual(alert, expAlert) {
 			t.Errorf("expected %v is equal to %v", alert, expAlert)
 		}
 
-		alert = &APIAlert{}
+		alert = &apiAlert{}
 		getResp(ts.URL+"/vmalert/"+expAlert.APILink(), alert, 200)
 		if !reflect.DeepEqual(alert, expAlert) {
 			t.Errorf("expected %v is equal to %v", alert, expAlert)
@@ -148,7 +146,7 @@ func TestHandler(t *testing.T) {
 }
 
 func TestEmptyResponse(t *testing.T) {
-	rhWithNoGroups := &requestHandler{m: &manager{groups: make(map[uint64]*Group)}}
+	rhWithNoGroups := &requestHandler{m: &manager{groups: make(map[uint64]*rule.Group)}}
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { rhWithNoGroups.handler(w, r) }))
 	defer ts.Close()
 
@@ -201,7 +199,7 @@ func TestEmptyResponse(t *testing.T) {
 		}
 	})
 
-	rhWithEmptyGroup := &requestHandler{m: &manager{groups: map[uint64]*Group{0: {Name: "test"}}}}
+	rhWithEmptyGroup := &requestHandler{m: &manager{groups: map[uint64]*rule.Group{0: {Name: "test"}}}}
 	ts.Config.Handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { rhWithEmptyGroup.handler(w, r) })
 
 	t.Run("empty group /api/v1/rules", func(t *testing.T) {
diff --git a/app/vmalert/web_types.go b/app/vmalert/web_types.go
index 4f4a8f911..7099c53e0 100644
--- a/app/vmalert/web_types.go
+++ b/app/vmalert/web_types.go
@@ -2,13 +2,28 @@ package main
 
 import (
 	"fmt"
+	"net/url"
+	"sort"
+	"strconv"
 	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
 )
 
-// APIAlert represents a notifier.AlertingRule state
+const (
+	// ParamGroupID is group id key in url parameter
+	paramGroupID = "group_id"
+	// ParamAlertID is alert id key in url parameter
+	paramAlertID = "alert_id"
+	// ParamRuleID is rule id key in url parameter
+	paramRuleID = "rule_id"
+)
+
+// apiAlert represents a notifier.AlertingRule state
 // for WEB view
 // https://github.com/prometheus/compliance/blob/main/alert_generator/specification.md#get-apiv1rules
-type APIAlert struct {
+type apiAlert struct {
 	State       string            `json:"state"`
 	Name        string            `json:"name"`
 	Value       string            `json:"value"`
@@ -38,24 +53,24 @@ type APIAlert struct {
 }
 
 // WebLink returns a link to the alert which can be used in UI.
-func (aa *APIAlert) WebLink() string {
+func (aa *apiAlert) WebLink() string {
 	return fmt.Sprintf("alert?%s=%s&%s=%s",
 		paramGroupID, aa.GroupID, paramAlertID, aa.ID)
 }
 
 // APILink returns a link to the alert's JSON representation.
-func (aa *APIAlert) APILink() string {
+func (aa *apiAlert) APILink() string {
 	return fmt.Sprintf("api/v1/alert?%s=%s&%s=%s",
 		paramGroupID, aa.GroupID, paramAlertID, aa.ID)
 }
 
-// APIGroup represents Group for WEB view
+// apiGroup represents Group for web view
 // https://github.com/prometheus/compliance/blob/main/alert_generator/specification.md#get-apiv1rules
-type APIGroup struct {
+type apiGroup struct {
 	// Name is the group name as present in the config
 	Name string `json:"name"`
 	// Rules contains both recording and alerting rules
-	Rules []APIRule `json:"rules"`
+	Rules []apiRule `json:"rules"`
 	// Interval is the Group's evaluation interval in float seconds as present in the file.
 	Interval float64 `json:"interval"`
 	// LastEvaluation is the timestamp of the last time the Group was executed
@@ -81,15 +96,15 @@ type APIGroup struct {
 	Labels map[string]string `json:"labels,omitempty"`
 }
 
-// GroupAlerts represents a group of alerts for WEB view
-type GroupAlerts struct {
-	Group  APIGroup
-	Alerts []*APIAlert
+// groupAlerts represents a group of alerts for WEB view
+type groupAlerts struct {
+	Group  apiGroup
+	Alerts []*apiAlert
 }
 
-// APIRule represents a Rule for WEB view
+// apiRule represents a Rule for web view
 // see https://github.com/prometheus/compliance/blob/main/alert_generator/specification.md#get-apiv1rules
-type APIRule struct {
+type apiRule struct {
 	// State must be one of these under following scenarios
 	//  "pending": at least 1 alert in the rule in pending state and no other alert in firing ruleState.
 	//  "firing": at least 1 alert in the rule in firing state.
@@ -111,7 +126,7 @@ type APIRule struct {
 	// LastEvaluation is the timestamp of the last time the rule was executed
 	LastEvaluation time.Time `json:"lastEvaluation"`
 	// Alerts  is the list of all the alerts in this rule that are currently pending or firing
-	Alerts []*APIAlert `json:"alerts,omitempty"`
+	Alerts []*apiAlert `json:"alerts,omitempty"`
 	// Health is the health of rule evaluation.
 	// It MUST be one of "ok", "err", "unknown"
 	Health string `json:"health"`
@@ -138,11 +153,206 @@ type APIRule struct {
 	// MaxUpdates is the max number of recorded ruleStateEntry objects
 	MaxUpdates int `json:"max_updates_entries"`
 	// Updates contains the ordered list of recorded ruleStateEntry objects
-	Updates []ruleStateEntry `json:"-"`
+	Updates []rule.StateEntry `json:"-"`
 }
 
 // WebLink returns a link to the alert which can be used in UI.
-func (ar APIRule) WebLink() string {
+func (ar apiRule) WebLink() string {
 	return fmt.Sprintf("rule?%s=%s&%s=%s",
 		paramGroupID, ar.GroupID, paramRuleID, ar.ID)
 }
+
+func ruleToAPI(r interface{}) apiRule {
+	if ar, ok := r.(*rule.AlertingRule); ok {
+		return alertingToAPI(ar)
+	}
+	if rr, ok := r.(*rule.RecordingRule); ok {
+		return recordingToAPI(rr)
+	}
+	return apiRule{}
+}
+
+func recordingToAPI(rr *rule.RecordingRule) apiRule {
+	lastState := rule.GetLastEntry(rr)
+	r := apiRule{
+		Type:              "recording",
+		DatasourceType:    rr.Type.String(),
+		Name:              rr.Name,
+		Query:             rr.Expr,
+		Labels:            rr.Labels,
+		LastEvaluation:    lastState.Time,
+		EvaluationTime:    lastState.Duration.Seconds(),
+		Health:            "ok",
+		LastSamples:       lastState.Samples,
+		LastSeriesFetched: lastState.SeriesFetched,
+		MaxUpdates:        rule.GetRuleStateSize(rr),
+		Updates:           rule.GetAllRuleState(rr),
+
+		// encode as strings to avoid rounding
+		ID:      fmt.Sprintf("%d", rr.ID()),
+		GroupID: fmt.Sprintf("%d", rr.GroupID),
+	}
+	if lastState.Err != nil {
+		r.LastError = lastState.Err.Error()
+		r.Health = "err"
+	}
+	return r
+}
+
+// alertingToAPI returns Rule representation in form of apiRule
+func alertingToAPI(ar *rule.AlertingRule) apiRule {
+	lastState := rule.GetLastEntry(ar)
+	r := apiRule{
+		Type:              "alerting",
+		DatasourceType:    ar.Type.String(),
+		Name:              ar.Name,
+		Query:             ar.Expr,
+		Duration:          ar.For.Seconds(),
+		KeepFiringFor:     ar.KeepFiringFor.Seconds(),
+		Labels:            ar.Labels,
+		Annotations:       ar.Annotations,
+		LastEvaluation:    lastState.Time,
+		EvaluationTime:    lastState.Duration.Seconds(),
+		Health:            "ok",
+		State:             "inactive",
+		Alerts:            ruleToAPIAlert(ar),
+		LastSamples:       lastState.Samples,
+		LastSeriesFetched: lastState.SeriesFetched,
+		MaxUpdates:        rule.GetRuleStateSize(ar),
+		Updates:           rule.GetAllRuleState(ar),
+		Debug:             ar.Debug,
+
+		// encode as strings to avoid rounding in JSON
+		ID:      fmt.Sprintf("%d", ar.ID()),
+		GroupID: fmt.Sprintf("%d", ar.GroupID),
+	}
+	if lastState.Err != nil {
+		r.LastError = lastState.Err.Error()
+		r.Health = "err"
+	}
+	// satisfy apiRule.State logic
+	if len(r.Alerts) > 0 {
+		r.State = notifier.StatePending.String()
+		stateFiring := notifier.StateFiring.String()
+		for _, a := range r.Alerts {
+			if a.State == stateFiring {
+				r.State = stateFiring
+				break
+			}
+		}
+	}
+	return r
+}
+
+// ruleToAPIAlert generates list of apiAlert objects from existing alerts
+func ruleToAPIAlert(ar *rule.AlertingRule) []*apiAlert {
+	var alerts []*apiAlert
+	for _, a := range ar.GetAlerts() {
+		if a.State == notifier.StateInactive {
+			continue
+		}
+		alerts = append(alerts, newAlertAPI(ar, a))
+	}
+	return alerts
+}
+
+// alertToAPI generates apiAlert object from alert by its id(hash)
+func alertToAPI(ar *rule.AlertingRule, id uint64) *apiAlert {
+	a := ar.GetAlert(id)
+	if a == nil {
+		return nil
+	}
+	return newAlertAPI(ar, a)
+}
+
+// NewAlertAPI creates apiAlert for notifier.Alert
+func newAlertAPI(ar *rule.AlertingRule, a *notifier.Alert) *apiAlert {
+	aa := &apiAlert{
+		// encode as strings to avoid rounding
+		ID:      fmt.Sprintf("%d", a.ID),
+		GroupID: fmt.Sprintf("%d", a.GroupID),
+		RuleID:  fmt.Sprintf("%d", ar.RuleID),
+
+		Name:        a.Name,
+		Expression:  ar.Expr,
+		Labels:      a.Labels,
+		Annotations: a.Annotations,
+		State:       a.State.String(),
+		ActiveAt:    a.ActiveAt,
+		Restored:    a.Restored,
+		Value:       strconv.FormatFloat(a.Value, 'f', -1, 32),
+	}
+	if alertURLGeneratorFn != nil {
+		aa.SourceLink = alertURLGeneratorFn(*a)
+	}
+	if a.State == notifier.StateFiring && !a.KeepFiringSince.IsZero() {
+		aa.Stabilizing = true
+	}
+	return aa
+}
+
+func groupToAPI(g *rule.Group) apiGroup {
+	g = g.DeepCopy()
+	ag := apiGroup{
+		// encode as string to avoid rounding
+		ID: fmt.Sprintf("%d", g.ID()),
+
+		Name:            g.Name,
+		Type:            g.Type.String(),
+		File:            g.File,
+		Interval:        g.Interval.Seconds(),
+		LastEvaluation:  g.LastEvaluation,
+		Concurrency:     g.Concurrency,
+		Params:          urlValuesToStrings(g.Params),
+		Headers:         headersToStrings(g.Headers),
+		NotifierHeaders: headersToStrings(g.NotifierHeaders),
+
+		Labels: g.Labels,
+	}
+	ag.Rules = make([]apiRule, 0)
+	for _, r := range g.Rules {
+		ag.Rules = append(ag.Rules, ruleToAPI(r))
+	}
+	return ag
+}
+
+func urlValuesToStrings(values url.Values) []string {
+	if len(values) < 1 {
+		return nil
+	}
+
+	keys := make([]string, 0, len(values))
+	for k := range values {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+
+	var res []string
+	for _, k := range keys {
+		params := values[k]
+		for _, v := range params {
+			res = append(res, fmt.Sprintf("%s=%s", k, v))
+		}
+	}
+	return res
+}
+
+func headersToStrings(headers map[string]string) []string {
+	if len(headers) < 1 {
+		return nil
+	}
+
+	keys := make([]string, 0, len(headers))
+	for k := range headers {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+
+	var res []string
+	for _, k := range keys {
+		v := headers[k]
+		res = append(res, fmt.Sprintf("%s: %s", k, v))
+	}
+
+	return res
+}
diff --git a/app/vmalert/web_types_test.go b/app/vmalert/web_types_test.go
new file mode 100644
index 000000000..48c747af6
--- /dev/null
+++ b/app/vmalert/web_types_test.go
@@ -0,0 +1,23 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestUrlValuesToStrings(t *testing.T) {
+	mapQueryParams := map[string][]string{
+		"param1": {"param1"},
+		"param2": {"anotherparam"},
+	}
+	expectedRes := []string{"param1=param1", "param2=anotherparam"}
+	res := urlValuesToStrings(mapQueryParams)
+
+	if len(res) != len(expectedRes) {
+		t.Errorf("Expected length %d, but got %d", len(expectedRes), len(res))
+	}
+	for ind, val := range expectedRes {
+		if val != res[ind] {
+			t.Errorf("Expected %v; but got %v", val, res[ind])
+		}
+	}
+}
diff --git a/docs/Articles.md b/docs/Articles.md
index 11df52803..c97dac65b 100644
--- a/docs/Articles.md
+++ b/docs/Articles.md
@@ -1,11 +1,11 @@
 ---
-sort: 20
-weight: 20
+sort: 29
+weight: 29
 title: Articles
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 20
+    parent: 'victoriametrics'
+    weight: 29
 aliases:
 - /Articles.html
 ---
diff --git a/docs/BestPractices.md b/docs/BestPractices.md
index d2737840d..e79e612de 100644
--- a/docs/BestPractices.md
+++ b/docs/BestPractices.md
@@ -1,11 +1,11 @@
 ---
-sort: 23
-weight: 23
+sort: 32
+weight: 32
 title: VictoriaMetrics best practices
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 23
+    parent: 'victoriametrics'
+    weight: 32
 aliases:
 - /BestPractices.html
 ---
diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index f93a1d261..6a037ad97 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -1,11 +1,11 @@
 ---
-sort: 16
-weight: 16
+sort: 25
+weight: 25
 title: CHANGELOG
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 16
+    parent: 'victoriametrics'
+    weight: 25
 aliases:
 - /CHANGELOG.html
 ---
@@ -44,8 +44,10 @@ The sandbox cluster installation is running under the constant load generated by
 * FEATURE: [vmui](https://docs.victoriametrics.com/#vmui): improve repeated VMUI page load times by enabling caching of static js and css at web browser side according to [these recommendations](https://developer.chrome.com/docs/lighthouse/performance/uses-long-cache-ttl/).
 * FEATURE: [vmui](https://docs.victoriametrics.com/#vmui): show information about lines with bigger values at the top of the legend under the graph in order to simplify graph analysis.
 * FEATURE: [vmui](https://docs.victoriametrics.com/#vmui): reduce vertical space usage, so more information is visible on the screen without scrolling.
+* FEATURE: [vmalert-tool](https://docs.victoriametrics.com/#vmalert-tool): add `unittest` command to run unittest for alerting and recording rules. See [this pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/4789) for details.
 
 * BUGFIX: [vmalert](https://docs.victoriametrics.com/vmalert.html): strip sensitive information such as auth headers or passwords from datasource, remote-read, remote-write or notifier URLs in log messages or UI. This behavior is by default and is controlled via `-datasource.showURL`, `-remoteRead.showURL`, `remoteWrite.showURL` or `-notifier.showURL` cmd-line flags. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5044).
+* BUGFIX: [vmalert](https://docs.victoriametrics.com/vmalert.html): fix vmalert web UI when running on 32-bit architectures machine.
 * BUGFIX: [vmselect](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html): improve performance and memory usage during query processing on machines with big number of CPU cores. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5087) for details.
 * BUGFIX: dashboards: fix vminsert/vmstorage/vmselect metrics filtering when dashboard is used to display data from many sub-clusters with unique job names. Before, only one specific job could have been accounted for component-specific panels, instead of all available jobs for the component.
 * BUGFIX: [VictoriaMetrics cluster](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html): bump hard-coded limit for search query size at `vmstorage` from 1MB to 5MB. The change should be more suitable for real-world scenarios and protect vmstorage from excessive memory usage. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5154) for details
diff --git a/docs/CHANGELOG_2020.md b/docs/CHANGELOG_2020.md
index b7c913928..67045edb9 100644
--- a/docs/CHANGELOG_2020.md
+++ b/docs/CHANGELOG_2020.md
@@ -1,11 +1,11 @@
 ---
-sort: 19
-weight: 19
+sort: 28
+weight: 28
 title: CHANGELOG for the year 2020
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 19
+    parent: 'victoriametrics'
+    weight: 28
 aliases:
 - /CHANGELOG.html
 ---
diff --git a/docs/CHANGELOG_2021.md b/docs/CHANGELOG_2021.md
index e02c10238..46b878c30 100644
--- a/docs/CHANGELOG_2021.md
+++ b/docs/CHANGELOG_2021.md
@@ -1,11 +1,11 @@
 ---
-sort: 18
-weight: 18
+sort: 27
+weight: 27
 title: CHANGELOG for the year 2021
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 18
+    parent: 'victoriametrics'
+    weight: 27
 aliases:
 - /CHANGELOG.html
 ---
diff --git a/docs/CHANGELOG_2022.md b/docs/CHANGELOG_2022.md
index 16d046eb4..d3366b9a5 100644
--- a/docs/CHANGELOG_2022.md
+++ b/docs/CHANGELOG_2022.md
@@ -1,11 +1,11 @@
 ---
-sort: 17
-weight: 17
+sort: 26
+weight: 26
 title: CHANGELOG for the year 2022
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 17
+    parent: 'victoriametrics'
+    weight: 26
 aliases:
 - /CHANGELOG.html
 ---
diff --git a/docs/CaseStudies.md b/docs/CaseStudies.md
index 6c2be657a..a3642ccf1 100644
--- a/docs/CaseStudies.md
+++ b/docs/CaseStudies.md
@@ -1,11 +1,11 @@
 ---
-sort: 12
-weight: 12
+sort: 21
+weight: 21
 title: Case studies and talks
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 12
+    parent: 'victoriametrics'
+    weight: 21
 aliases:
 - /CaseStudies.html
 ---
diff --git a/docs/FAQ.md b/docs/FAQ.md
index 466982bb2..d57c428b0 100644
--- a/docs/FAQ.md
+++ b/docs/FAQ.md
@@ -1,11 +1,11 @@
 ---
-sort: 15
-weight: 15
+sort: 24
+weight: 24
 title: FAQ
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 15
+    parent: 'victoriametrics'
+    weight: 24
 aliases:
 - /FAQ.html
 ---
diff --git a/docs/MetricsQL.md b/docs/MetricsQL.md
index 81df16782..4a6248458 100644
--- a/docs/MetricsQL.md
+++ b/docs/MetricsQL.md
@@ -1,11 +1,11 @@
 ---
-sort: 14
-weight: 14
+sort: 23
+weight: 23
 title: MetricsQL
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 14
+    parent: 'victoriametrics'
+    weight: 23
 aliases:
 - /ExtendedPromQL.html
 - /MetricsQL.html
diff --git a/docs/PerTenantStatistic.md b/docs/PerTenantStatistic.md
index 9ad033ec6..3be89eb6a 100644
--- a/docs/PerTenantStatistic.md
+++ b/docs/PerTenantStatistic.md
@@ -1,11 +1,11 @@
 ---
-sort: 22
-weight: 22
+sort: 31
+weight: 31
 title: VictoriaMetrics Cluster Per Tenant Statistic
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 22
+    parent: 'victoriametrics'
+    weight: 31
 aliases:
 - /PerTenantStatistic.html
 ---
diff --git a/docs/Quick-Start.md b/docs/Quick-Start.md
index c48b42049..55e332e78 100644
--- a/docs/Quick-Start.md
+++ b/docs/Quick-Start.md
@@ -1,11 +1,11 @@
 ---
-sort: 13
-weight: 13
+sort: 22
+weight: 22
 title: Quick start
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 13
+    parent: 'victoriametrics'
+    weight: 22
 aliases:
 - /Quick-Start.html
 ---
diff --git a/docs/Release-Guide.md b/docs/Release-Guide.md
index 2399688d9..6ebfec621 100644
--- a/docs/Release-Guide.md
+++ b/docs/Release-Guide.md
@@ -1,11 +1,11 @@
 ---
-sort: 21
-weight: 21
+sort: 30
+weight: 30
 title: Release process guidance
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 21
+    parent: 'victoriametrics'
+    weight: 30
 aliases:
 - /Release-Guide.html
 ---
diff --git a/docs/Troubleshooting.md b/docs/Troubleshooting.md
index e05bf9770..587740b41 100644
--- a/docs/Troubleshooting.md
+++ b/docs/Troubleshooting.md
@@ -1,11 +1,11 @@
 ---
-sort: 26
-weight: 26
+sort: 35
+weight: 35
 title: Troubleshooting
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 26
+    parent: 'victoriametrics'
+    weight: 35
 aliases:
 - /Troubleshooting.html
 ---
diff --git a/docs/enterprise.md b/docs/enterprise.md
index f5a17f59a..c79e98643 100644
--- a/docs/enterprise.md
+++ b/docs/enterprise.md
@@ -4,7 +4,7 @@ weight: 99
 title: VictoriaMetrics Enterprise
 menu:
   docs:
-    parent: "victoriametrics"
+    parent: 'victoriametrics'
     weight: 99
 aliases:
 - /enterprise.html
diff --git a/docs/keyConcepts.md b/docs/keyConcepts.md
index aca976cfe..c8e0a60d1 100644
--- a/docs/keyConcepts.md
+++ b/docs/keyConcepts.md
@@ -1,11 +1,11 @@
 ---
-sort: 25
-weight: 25
+sort: 34
+weight: 34
 title: Key concepts
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 25
+    parent: 'victoriametrics'
+    weight: 34
 aliases:
 - /keyConcepts.html
 ---
diff --git a/docs/relabeling.md b/docs/relabeling.md
index 97b103913..1900e251d 100644
--- a/docs/relabeling.md
+++ b/docs/relabeling.md
@@ -1,11 +1,11 @@
 ---
-sort: 28
-weight: 28
+sort: 37
+weight: 37
 title: Relabeling cookbook
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 25
+    parent: 'victoriametrics'
+    weight: 37
 aliases:
 - /relabeling.html
 ---
diff --git a/docs/sd_configs.md b/docs/sd_configs.md
index d697e5eec..a45ac61cf 100644
--- a/docs/sd_configs.md
+++ b/docs/sd_configs.md
@@ -1,11 +1,11 @@
 ---
-sort: 27
-weight: 27
+sort: 36
+weight: 36
 title: Prometheus service discovery
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 27
+    parent: 'victoriametrics'
+    weight: 36
 aliases:
 - /sd_configs.html
 ---
diff --git a/docs/stream-aggregation.md b/docs/stream-aggregation.md
index 159986fde..504a8f5b4 100644
--- a/docs/stream-aggregation.md
+++ b/docs/stream-aggregation.md
@@ -4,7 +4,7 @@ weight: 98
 title: Streaming aggregation
 menu:
   docs:
-    parent: "victoriametrics"
+    parent: 'victoriametrics'
     weight: 98
 aliases:
 - /stream-aggregation.html
diff --git a/docs/url-examples.md b/docs/url-examples.md
index f1bded5aa..d20177a08 100644
--- a/docs/url-examples.md
+++ b/docs/url-examples.md
@@ -1,11 +1,11 @@
 ---
-sort: 24
-weight: 24
+sort: 33
+weight: 33
 title: VictoriaMetrics API examples
 menu:
   docs:
-    parent: "victoriametrics"
-    weight: 24
+    parent: 'victoriametrics'
+    weight: 33
 ---
 
 # VictoriaMetrics API examples
diff --git a/docs/vmalert-tool.md b/docs/vmalert-tool.md
new file mode 100644
index 000000000..7ee418b5e
--- /dev/null
+++ b/docs/vmalert-tool.md
@@ -0,0 +1,253 @@
+---
+sort: 12
+weight: 12
+menu:
+  docs:
+    parent: 'victoriametrics'
+    weight: 12
+title: vmalert-tool
+---
+
+# vmalert-tool
+
+VMAlert command-line tool
+
+## Unit testing for rules
+
+You can use `vmalert-tool` to run unit tests for alerting and recording rules.
+It will perform the following actions:
+* sets up an isolated VictoriaMetrics instance;
+* simulates the periodic ingestion of time series;
+* queries the ingested data for recording and alerting rules evaluation like [vmalert](https://docs.victoriametrics.com/vmalert.html);
+* checks whether the firing alerts or resulting recording rules match the expected results.
+
+See how to run vmalert-tool for unit test below:
+```
+# Run vmalert-tool with one or multiple test files via --files cmd-line flag
+./vmalert-tool unittest --files test1.yaml --files test2.yaml
+```
+
+vmalert-tool unittest is compatible with [Prometheus config format for tests](https://prometheus.io/docs/prometheus/latest/configuration/unit_testing_rules/#test-file-format)
+except `promql_expr_test` field. Use `metricsql_expr_test` field name instead. The name is different because vmalert-tool
+validates and executes [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html) expressions,
+which aren't always backward compatible with [PromQL](https://prometheus.io/docs/prometheus/latest/querying/basics/).
+
+### Test file format
+
+The configuration format for files specified in `--files` cmd-line flag is the following:
+```
+# Path to the files or http url containing [rule groups](https://docs.victoriametrics.com/vmalert.html#groups) configuration.
+# Enterprise version of vmalert-tool supports S3 and GCS paths to rules.
+rule_files:
+  [ - <string> ]
+
+# The evaluation interval for rules specified in `rule_files`
+[ evaluation_interval: <duration> | default = 1m ]
+
+# Groups listed below will be evaluated by order.
+# Not All the groups need not be mentioned, if not, they will be evaluated by define order in rule_files.
+group_eval_order:
+  [ - <string> ]
+
+# The list of unit test files to be checked during evaluation.
+tests:
+  [ - <test_group> ]
+```
+
+#### `<test_group>`
+
+```
+# Interval between samples for input series
+interval: <duration>
+# Time series to persist into the database according to configured <interval> before running tests.
+input_series:
+  [ - <series> ]
+
+# Name of the test group, optional
+[ name: <string> ]
+
+# Unit tests for alerting rules
+alert_rule_test:
+  [ - <alert_test_case> ]
+
+# Unit tests for Metricsql expressions.
+metricsql_expr_test:
+  [ - <metricsql_expr_test> ]
+
+# External labels accessible for templating.
+external_labels:
+  [ <labelname>: <string> ... ]
+
+```
+
+#### `<series>`
+
+```
+# series in the following format '<metric name>{<label name>=<label value>, ...}'
+# Examples:
+#      series_name{label1="value1", label2="value2"}
+#      go_goroutines{job="prometheus", instance="localhost:9090"}
+series: <string>
+
+# values support several special equations:
+#    'a+bxc' becomes 'a a+b a+(2*b) a+(3*b) … a+(c*b)'
+#     Read this as series starts at a, then c further samples incrementing by b.
+#    'a-bxc' becomes 'a a-b a-(2*b) a-(3*b) … a-(c*b)'
+#     Read this as series starts at a, then c further samples decrementing by b (or incrementing by negative b).
+#    '_' represents a missing sample from scrape
+#    'stale' indicates a stale sample
+# Examples:
+#     1. '-2+4x3' becomes '-2 2 6 10' - series starts at -2, then 3 further samples incrementing by 4.
+#     2. ' 1-2x4' becomes '1 -1 -3 -5 -7' - series starts at 1, then 4 further samples decrementing by 2.
+#     3. ' 1x4' becomes '1 1 1 1 1' - shorthand for '1+0x4', series starts at 1, then 4 further samples incrementing by 0.
+#     4. ' 1 _x3 stale' becomes '1 _ _ _ stale' - the missing sample cannot increment, so 3 missing samples are produced by the '_x3' expression.
+values: <string>
+```
+
+#### `<alert_test_case>`
+
+vmalert by default adds `alertgroup` and `alertname` to the generated alerts and time series.
+So you will need to specify both `groupname` and `alertname` under a single `<alert_test_case>`,
+but no need to add them under `exp_alerts`.
+You can also pass `--disableAlertgroupLabel` to skip `alertgroup` check.
+
+```
+# The time elapsed from time=0s when this alerting rule should be checked.
+# Means this rule should be firing at this point, or shouldn't be firing if 'exp_alerts' is empty.
+eval_time: <duration>
+
+# Name of the group name to be tested.
+groupname: <string>
+
+# Name of the alert to be tested.
+alertname: <string>
+
+# List of the expected alerts that are firing under the given alertname at
+# the given evaluation time. If you want to test if an alerting rule should
+# not be firing, then you can mention only the fields above and leave 'exp_alerts' empty.
+exp_alerts:
+  [ - <alert> ]
+```
+
+#### `<alert>`
+
+```
+# These are the expanded labels and annotations of the expected alert.
+# Note: labels also include the labels of the sample associated with the alert
+exp_labels:
+  [ <labelname>: <string> ]
+exp_annotations:
+  [ <labelname>: <string> ]
+```
+
+#### `<metricsql_expr_test>`
+
+```
+# Expression to evaluate
+expr: <string>
+
+# The time elapsed from time=0s when this expression be evaluated.
+eval_time: <duration>
+
+# Expected samples at the given evaluation time.
+exp_samples:
+  [ - <sample> ]
+```
+
+#### `<sample>`
+
+```
+# Labels of the sample in usual series notation '<metric name>{<label name>=<label value>, ...}'
+# Examples:
+#      series_name{label1="value1", label2="value2"}
+#      go_goroutines{job="prometheus", instance="localhost:9090"}
+labels: <string>
+
+# The expected value of the Metricsql expression.
+value: <number>
+```
+
+### Example
+
+This is an example input file for unit testing which will pass.
+`test.yaml` is the test file which follows the syntax above and `alerts.yaml` contains the alerting rules.
+
+With `rules.yaml` in the same directory, run `./vmalert-tool unittest --files=./unittest/testdata/test.yaml`.
+
+#### `test.yaml`
+
+```
+rule_files:
+  - rules.yaml
+
+evaluation_interval: 1m
+
+tests:
+  - interval: 1m
+    input_series:
+      - series: 'up{job="prometheus", instance="localhost:9090"}'
+        values: "0+0x1440"
+
+    metricsql_expr_test:
+      - expr: suquery_interval_test
+        eval_time: 4m
+        exp_samples:
+          - labels: '{__name__="suquery_interval_test", datacenter="dc-123", instance="localhost:9090", job="prometheus"}'
+            value: 1
+
+    alert_rule_test:
+      - eval_time: 2h
+        groupname: group1
+        alertname: InstanceDown
+        exp_alerts:
+          - exp_labels:
+              job: prometheus
+              severity: page
+              instance: localhost:9090
+              datacenter: dc-123
+            exp_annotations:
+              summary: "Instance localhost:9090 down"
+              description: "localhost:9090 of job prometheus has been down for more than 5 minutes."
+
+      - eval_time: 0
+        groupname: group1
+        alertname: AlwaysFiring
+        exp_alerts:
+          - exp_labels:
+              datacenter: dc-123
+
+      - eval_time: 0
+        groupname: group1
+        alertname: InstanceDown
+        exp_alerts: []
+
+    external_labels:
+      datacenter: dc-123
+```
+
+#### `alerts.yaml`
+
+```
+# This is the rules file.
+
+groups:
+  - name: group1
+    rules:
+      - alert: InstanceDown
+        expr: up == 0
+        for: 5m
+        labels:
+          severity: page
+        annotations:
+          summary: "Instance {{ $labels.instance }} down"
+          description: "{{ $labels.instance }} of job {{ $labels.job }} has been down for more than 5 minutes."
+      - alert: AlwaysFiring
+        expr: 1
+
+  - name: group2
+    rules:
+      - record: job:test:count_over_time1m
+        expr: sum without(instance) (count_over_time(test[1m]))
+      - record: suquery_interval_test
+        expr: count_over_time(up[5m:])
+```
\ No newline at end of file
diff --git a/docs/vmalert.md b/docs/vmalert.md
index d3e3261d3..5265d565e 100644
--- a/docs/vmalert.md
+++ b/docs/vmalert.md
@@ -765,6 +765,11 @@ See full description for these flags in `./vmalert -help`.
 * `limit` group's param has no effect during replay (might be changed in future);
 * `keep_firing_for` alerting rule param has no effect during replay (might be changed in future).
 
+## Unit Testing for Rules
+
+You can use `vmalert-tool` to test your alerting and recording rules like [promtool does](https://prometheus.io/docs/prometheus/latest/configuration/unit_testing_rules/).
+See more details [here](https://docs.victoriametrics.com/vmalert-tool.html#Unit-testing-for-rules).
+
 ## Monitoring
 
 `vmalert` exports various metrics in Prometheus exposition format at `http://vmalert-host:8880/metrics` page.
diff --git a/docs/vmanomaly.md b/docs/vmanomaly.md
index f0f71b42d..bdfdf7489 100644
--- a/docs/vmanomaly.md
+++ b/docs/vmanomaly.md
@@ -4,7 +4,7 @@ weight: 11
 title: vmanomaly
 menu:
   docs:
-    parent: "victoriametrics"
+    parent: 'victoriametrics'
     weight: 11
 aliases:
 - /vmanomaly.html
diff --git a/lib/promutils/duration.go b/lib/promutils/duration.go
index 2fc57c52e..565e592f1 100644
--- a/lib/promutils/duration.go
+++ b/lib/promutils/duration.go
@@ -53,3 +53,11 @@ func ParseDuration(s string) (time.Duration, error) {
 	}
 	return time.Duration(ms) * time.Millisecond, nil
 }
+
+// ParseTime returns time for pd.
+func (pd *Duration) ParseTime() time.Time {
+	if pd == nil {
+		return time.Time{}
+	}
+	return time.UnixMilli(pd.Duration().Milliseconds())
+}