diff --git a/builtin-base.go b/builtin-base.go
index c52d657..3077e0f 100644
--- a/builtin-base.go
+++ b/builtin-base.go
@@ -236,6 +236,35 @@ func varFunc(ctx ExprContext, name string, args map[string]any) (result any, err
 	return
 }
 
+func setFunc(ctx ExprContext, name string, args map[string]any) (result any, err error) {
+	var varName string
+	var ok bool
+
+	if varName, ok = args[ParamName].(string); !ok {
+		return nil, ErrWrongParamType(name, ParamName, TypeString, args[ParamName])
+	}
+
+	if result, ok = args[ParamValue]; ok {
+		ctx.GetParent().UnsafeSetVar(varName, result)
+	} else {
+		err = ErrWrongParamType(name, ParamValue, TypeAny, args[ParamValue])
+	}
+	return
+}
+
+func unsetFunc(ctx ExprContext, name string, args map[string]any) (result any, err error) {
+	var varName string
+	var ok bool
+
+	if varName, ok = args[ParamName].(string); !ok {
+		return nil, ErrWrongParamType(name, ParamName, TypeString, args[ParamName])
+	} else {
+		ctx.GetParent().DeleteVar(varName)
+		result = nil
+	}
+	return
+}
+
 //// import
 
 func ImportBuiltinsFuncs(ctx ExprContext) {
@@ -270,6 +299,16 @@ func ImportBuiltinsFuncs(ctx ExprContext) {
 		NewFuncParam(ParamName),
 		NewFuncParamFlagDef(ParamValue, PfDefault, nil),
 	})
+
+	ctx.RegisterFunc("set", NewGolangFunctor(setFunc), TypeAny, []ExprFuncParam{
+		NewFuncParam(ParamName),
+		NewFuncParam(ParamValue),
+	})
+
+	ctx.RegisterFunc("unset", NewGolangFunctor(unsetFunc), TypeAny, []ExprFuncParam{
+		NewFuncParam(ParamName),
+		NewFuncParam(ParamValue),
+	})
 }
 
 func init() {