diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index d6f3369e..54067d1d 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Release History
 
+## v4.0.0-beta2 (2022-04-25)
+
+**go version**
+
+- feat: add builtin function `environ`/`ENV`
+- fix: demo function compatibility
+
 ## v4.0.0-beta (2022-04-24)
 
 - refactor: merge [hrp] into httprunner v4, which will include golang and python dual engine
diff --git a/hrp/internal/builtin/function.go b/hrp/internal/builtin/function.go
index dd1fca1b..7be081dc 100644
--- a/hrp/internal/builtin/function.go
+++ b/hrp/internal/builtin/function.go
@@ -5,6 +5,7 @@ import (
 	"encoding/hex"
 	"math"
 	"math/rand"
+	"os"
 	"time"
 )
 
@@ -16,6 +17,8 @@ var Functions = map[string]interface{}{
 	"md5":               MD5,             // call with one argument
 	"parameterize":      loadFromCSV,
 	"P":                 loadFromCSV,
+	"environ":           os.Getenv,
+	"ENV":               os.Getenv,
 	"load_ws_message":   loadMessage,
 }