diff --git a/pkg/lang/ir/compile.go b/pkg/lang/ir/compile.go
index cc01690bd..62b16aed6 100644
--- a/pkg/lang/ir/compile.go
+++ b/pkg/lang/ir/compile.go
@@ -296,7 +296,10 @@ func (g Graph) Compile(uid, gid int) (llb.State, error) {
 	run := g.compileRun(copy)
 	git := g.compileGit(run)
 	user := g.compileUserOwn(git)
-	entrypoint := g.compileEntrypoint(user)
+	entrypoint, err := g.compileEntrypoint(user)
+	if err != nil {
+		return llb.State{}, errors.Wrap(err, "failed to compile entrypoint")
+	}
 	g.Writer.Finish()
 	return entrypoint, nil
 }
diff --git a/pkg/lang/ir/supervisor.go b/pkg/lang/ir/supervisor.go
index cee444597..246cc29e2 100644
--- a/pkg/lang/ir/supervisor.go
+++ b/pkg/lang/ir/supervisor.go
@@ -19,6 +19,7 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/cockroachdb/errors"
 	"github.com/moby/buildkit/client/llb"
 
 	"github.com/tensorchord/envd/pkg/config"
@@ -78,9 +79,12 @@ func (g Graph) addNewProcess(root llb.State, name, command string, depends []str
 	return supervisor
 }
 
-func (g Graph) compileEntrypoint(root llb.State) llb.State {
+func (g Graph) compileEntrypoint(root llb.State) (llb.State, error) {
 	if g.Image != nil {
-		return root
+		return root, nil
+	}
+	if len(g.Entrypoint) > 0 {
+		return root, errors.New("`config.entrypoint` is only for custom image, maybe you need `runtime.init`")
 	}
 	cmd := fmt.Sprintf("/var/envd/bin/envd-sshd --port %d --shell %s", config.SSHPortInContainer, g.Shell)
 	entrypoint := g.addNewProcess(root, "sshd", cmd, nil)
@@ -108,5 +112,5 @@ func (g Graph) compileEntrypoint(root llb.State) llb.State {
 		entrypoint = g.addNewProcess(entrypoint, "rstudio", strings.Join(rstudioCmd, " "), deps)
 	}
 
-	return entrypoint
+	return entrypoint, nil
 }