diff --git a/.gitignore b/.gitignore
index ce5deac..32e9aae 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,3 +10,4 @@ __pycache__/
 *.tmp.*
 host-config.json
 host-config-real.json
+host-state-real.json.bak*
diff --git a/tests/test_host.py b/tests/test_host.py
index 844f8f4..ccb7698 100644
--- a/tests/test_host.py
+++ b/tests/test_host.py
@@ -1,5 +1,6 @@
 import json
 import os
+import shutil
 import subprocess
 import sys
 import tempfile
@@ -93,7 +94,7 @@ class MergeVerifyTest(unittest.TestCase):
                 "        self.assertEqual(f(), 1)\n")
         (tests_dir / "test_mod.py").write_text(body, encoding="utf-8")
         subprocess.run(["git", "add", "-A"], cwd=tmp, check=True)
-        subprocess.run(["git", "commit", "-qm", "initial"], cwd=tmp,
+        subprocess.run(["git", "-c", "user.name=Test", "-c", "user.email=test@example.com", "commit", "-qm", "initial"], cwd=tmp,
                        check=True)
         # worktree 手动建：模拟 host 的 worktree/分支
         subprocess.run(["git", "worktree", "add", os.path.join(tmp, "wt"),
@@ -142,7 +143,7 @@ class MergeVerifyTest(unittest.TestCase):
             Path(tmp, "mod.py").write_text("def f():\n    return 1\n",
                                            encoding="utf-8")
             subprocess.run(["git", "add", "-A"], cwd=tmp, check=True)
-            subprocess.run(["git", "commit", "-qm", "initial"], cwd=tmp,
+            subprocess.run(["git", "-c", "user.name=Test", "-c", "user.email=test@example.com", "commit", "-qm", "initial"], cwd=tmp,
                            check=True)
             # 分支1：加 add2
             subprocess.run(["git", "worktree", "add",
@@ -273,9 +274,12 @@ class StateVersionTest(unittest.TestCase):
 
 
 class ServerRestartTest(unittest.TestCase):
+    @unittest.skipUnless(shutil.which("codex"),
+                         "codex binary not on PATH (e.g. GitHub runner)")
     def test_kill_then_ensure_alive(self):
         # 不跑模型：只验证 server 进程死了能重拉、list 能通。
         # 用配对二进制（VM 本机补丁），隔离 CODEX_HOME。
+        # Runner 上没有 codex 二进制时跳过，而不是失败。
         import host as host_mod
         with tempfile.TemporaryDirectory() as tmp:
             codex_home = os.path.join(tmp, "codex-home")
@@ -458,7 +462,7 @@ class GithubPRTest(unittest.TestCase):
             _init_git_repo(tmp)
             Path(tmp, "f.txt").write_text("x\n")
             subprocess.run(["git", "add", "-A"], cwd=tmp, check=True)
-            subprocess.run(["git", "commit", "-qm", "initial"],
+            subprocess.run(["git", "-c", "user.name=Test", "-c", "user.email=test@example.com", "commit", "-qm", "initial"],
                            cwd=tmp, check=True)
             task = {"name": "t", "branch": "host/t", "status": "completed",
                     "prompt": "do it"}
@@ -473,12 +477,12 @@ class GithubPRTest(unittest.TestCase):
             _init_git_repo(repo)
             Path(repo, "f.txt").write_text("x\n")
             subprocess.run(["git", "add", "-A"], cwd=repo, check=True)
-            subprocess.run(["git", "commit", "-qm", "initial"],
+            subprocess.run(["git", "-c", "user.name=Test", "-c", "user.email=test@example.com", "commit", "-qm", "initial"],
                            cwd=repo, check=True)
             subprocess.run(["git", "checkout", "-qb", "host/t1"],
                            cwd=repo, check=True)
             Path(repo, "f.txt").write_text("y\n")
-            subprocess.run(["git", "commit", "-qam", "change"],
+            subprocess.run(["git", "-c", "user.name=Test", "-c", "user.email=test@example.com", "commit", "-qam", "change"],
                            cwd=repo, check=True)
             remote = os.path.join(tmp, "remote.git")
             subprocess.run(["git", "init", "--bare", "-q", remote],