build(release): enable DEFLATE compression

script/release.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"archive/zip"
+	"compress/flate"
 	"crypto/sha256"
 	"encoding/hex"
 	"errors"
@@ -15,6 +16,7 @@ import (
 
 const (
 	checksumFilename = "SHA256SUMS.txt"
+	deflateLevel     = 6
 	dirPerms         = 0o755
 	distDir          = "dist"
 	filePerms        = 0o644
@@ -159,6 +161,9 @@ func zipDirectory(zipPath, dirPath string) error {
 	defer zipFile.Close()
 
 	zipWriter := zip.NewWriter(zipFile)
+	zipWriter.RegisterCompressor(zip.Deflate, func(out io.Writer) (io.WriteCloser, error) {
+		return flate.NewWriter(out, deflateLevel)
+	})
 	defer zipWriter.Close()
 
 	err = filepath.Walk(dirPath, func(path string, info fs.FileInfo, err error) error {
@@ -221,7 +226,7 @@ func appendChecksum(checksumFilePath, filePath string) error {
 
 	relPath, err := filepath.Rel(filepath.Dir(checksumFilePath), filePath)
 	if err != nil {
-			return fmt.Errorf("failed to get relative path: %v", err)
+		return fmt.Errorf("failed to get relative path: %v", err)
 	}
 	checksumLine := fmt.Sprintf("%s  %s\n", hash, relPath)