diff --git a/lib/encoding/compress.go b/lib/encoding/compress.go
index 6d3a050c3..3761982ee 100644
--- a/lib/encoding/compress.go
+++ b/lib/encoding/compress.go
@@ -4,14 +4,6 @@ import (
 	"github.com/valyala/gozstd"
 )
 
-// CompressZSTD compresses src, appends the result to dst and returns
-// the appended dst.
-//
-// src must be non-empty.
-func CompressZSTD(dst, src []byte) []byte {
-	return gozstd.CompressLevel(dst, src, 5)
-}
-
 // CompressZSTDLevel appends compressed src to dst and returns
 // the appended dst.
 //
diff --git a/lib/encoding/compress_test.go b/lib/encoding/compress_test.go
index 48224ea72..f959f1be3 100644
--- a/lib/encoding/compress_test.go
+++ b/lib/encoding/compress_test.go
@@ -17,7 +17,7 @@ func TestCompressDecompressZSTD(t *testing.T) {
 }
 
 func testCompressDecompressZSTD(t *testing.T, b []byte) {
-	bc := CompressZSTD(nil, b)
+	bc := CompressZSTDLevel(nil, b, 5)
 	bNew, err := DecompressZSTD(nil, bc)
 	if err != nil {
 		t.Fatalf("unexpected error when decompressing b=%x from bc=%x: %s", b, bc, err)
@@ -27,7 +27,7 @@ func testCompressDecompressZSTD(t *testing.T, b []byte) {
 	}
 
 	prefix := []byte{1, 2, 33}
-	bcNew := CompressZSTD(prefix, b)
+	bcNew := CompressZSTDLevel(prefix, b, 5)
 	if string(bcNew[:len(prefix)]) != string(prefix) {
 		t.Fatalf("invalid prefix for b=%x; got\n%x; expecting\n%x", b, bcNew[:len(prefix)], prefix)
 	}