diff --git a/cmd/joj3/conf.go b/cmd/joj3/conf.go
index 40dff6b..4f9951f 100644
--- a/cmd/joj3/conf.go
+++ b/cmd/joj3/conf.go
@@ -10,9 +10,11 @@ import (
 )
 
 type Conf struct {
-	LogLevel   int    `default:"0"`
-	OutputPath string `default:"joj3_result.json"`
-	Stages     []struct {
+	SandboxExecServer string `default:"localhost:5051"`
+	SandboxToken      string `default:""`
+	LogLevel          int    `default:"0"`
+	OutputPath        string `default:"joj3_result.json"`
+	Stages            []struct {
 		Name     string
 		Executor struct {
 			Name string
diff --git a/cmd/joj3/main.go b/cmd/joj3/main.go
index e21a52d..b8e0e05 100644
--- a/cmd/joj3/main.go
+++ b/cmd/joj3/main.go
@@ -5,7 +5,7 @@ import (
 	"log/slog"
 	"os"
 
-	_ "focs.ji.sjtu.edu.cn/git/FOCS-dev/JOJ3/internal/executors"
+	"focs.ji.sjtu.edu.cn/git/FOCS-dev/JOJ3/internal/executors"
 	_ "focs.ji.sjtu.edu.cn/git/FOCS-dev/JOJ3/internal/parsers"
 	"focs.ji.sjtu.edu.cn/git/FOCS-dev/JOJ3/internal/stage"
 
@@ -77,6 +77,7 @@ func main() {
 		os.Exit(1)
 	}
 	setupSlog(conf)
+	executors.InitWithConf(conf.SandboxExecServer, conf.SandboxToken)
 	stages := generateStages(conf)
 	defer stage.Cleanup()
 	results := stage.Run(stages)
diff --git a/internal/executors/all.go b/internal/executors/all.go
index bd860e6..76a7f96 100644
--- a/internal/executors/all.go
+++ b/internal/executors/all.go
@@ -2,8 +2,13 @@ package executors
 
 import (
 	_ "focs.ji.sjtu.edu.cn/git/FOCS-dev/JOJ3/internal/executors/dummy"
-	_ "focs.ji.sjtu.edu.cn/git/FOCS-dev/JOJ3/internal/executors/sandbox"
+	"focs.ji.sjtu.edu.cn/git/FOCS-dev/JOJ3/internal/executors/sandbox"
 )
 
 // this file does nothing but imports to ensure all the init() functions
 // in the subpackages are called
+
+// overwrite the default registered executors
+func InitWithConf(sandboxExecServer, sandboxToken string) {
+	sandbox.InitWithConf(sandboxExecServer, sandboxToken)
+}
diff --git a/internal/executors/sandbox/meta.go b/internal/executors/sandbox/meta.go
index 2702646..e984184 100644
--- a/internal/executors/sandbox/meta.go
+++ b/internal/executors/sandbox/meta.go
@@ -8,9 +8,17 @@ var name = "sandbox"
 
 func init() {
 	stage.RegisterExecutor(name, &Sandbox{
-		// TODO: read from conf
 		execServer: "localhost:5051",
 		token:      "",
 		cachedMap:  make(map[string]string),
 	})
 }
+
+// overwrite the default registered executor
+func InitWithConf(execServer, token string) {
+	stage.RegisterExecutor(name, &Sandbox{
+		execServer: execServer,
+		token:      token,
+		cachedMap:  make(map[string]string),
+	})
+}