diff --git a/bot_bottle/backend/docker/util.py b/bot_bottle/backend/docker/util.py
index f9ce729..af955f5 100644
--- a/bot_bottle/backend/docker/util.py
+++ b/bot_bottle/backend/docker/util.py
@@ -7,6 +7,7 @@ from __future__ import annotations
 import re
 import shutil
 import subprocess
+import tempfile
 from typing import Iterable, Iterator
 
 from ...log import die, info
@@ -130,17 +131,26 @@ def build_image_with_cwd(
     if not os.path.isdir(cwd):
         die(f"cwd not found at {cwd}")
     info(f"building image {derived} from {base} with {cwd} -> {workspace.guest_path}")
-    dockerfile = (
-        f"FROM {base}\n"
-        f"COPY --chown=node:node . {workspace.guest_path}\n"
-        f"WORKDIR {workspace.workdir}\n"
-    )
-    subprocess.run(
-        ["docker", "build", "-t", derived, "-f", "-", cwd],
-        input=dockerfile,
-        text=True,
-        check=True,
-    )
+    with tempfile.TemporaryDirectory(prefix="bot-bottle-cwd.") as tmp:
+        context_dir = os.path.join(tmp, "context")
+        staged_workspace = os.path.join(context_dir, "workspace")
+        shutil.copytree(
+            cwd,
+            staged_workspace,
+            symlinks=True,
+            ignore=shutil.ignore_patterns(".git"),
+        )
+        dockerfile = (
+            f"FROM {base}\n"
+            f"COPY --chown=node:node workspace/. {workspace.guest_path}\n"
+            f"WORKDIR {workspace.workdir}\n"
+        )
+        subprocess.run(
+            ["docker", "build", "-t", derived, "-f", "-", context_dir],
+            input=dockerfile,
+            text=True,
+            check=True,
+        )
 
 
 def image_id(ref: str) -> str:
diff --git a/tests/unit/test_docker_util_image.py b/tests/unit/test_docker_util_image.py
index a230290..941bebf 100644
--- a/tests/unit/test_docker_util_image.py
+++ b/tests/unit/test_docker_util_image.py
@@ -85,11 +85,45 @@ class TestBuildImageWithCwd(unittest.TestCase):
 
         argv = run.call_args.args[0]
         dockerfile = run.call_args.kwargs["input"]
-        self.assertEqual(["docker", "build", "-t", "derived:tag", "-f", "-", tmp], argv)
+        self.assertEqual(["docker", "build", "-t", "derived:tag", "-f", "-"], argv[:6])
+        self.assertTrue(argv[6].endswith("/context"))
         self.assertIn("FROM base:tag\n", dockerfile)
-        self.assertIn("COPY --chown=node:node . /guest/home/workspace\n", dockerfile)
+        self.assertIn(
+            "COPY --chown=node:node workspace/. /guest/home/workspace\n",
+            dockerfile,
+        )
         self.assertIn("WORKDIR /guest/home/workspace\n", dockerfile)
 
+    def test_staged_context_includes_hidden_files_but_not_git_dir(self):
+        with tempfile.TemporaryDirectory(prefix="bb-docker-cwd.") as tmp:
+            root = Path(tmp)
+            (root / ".gitignore").write_text("*.pyc\n")
+            (root / ".dockerignore").write_text(".gitignore\n")
+            (root / ".env.example").write_text("SAFE=1\n")
+            (root / ".git").mkdir()
+            (root / ".git" / "config").write_text("[core]\n")
+            workspace = WorkspacePlan(
+                enabled=True,
+                host_path=root,
+                guest_home="/guest/home",
+                guest_path="/guest/home/workspace",
+                workdir="/guest/home/workspace",
+            )
+
+            def inspect_context(*args, **kwargs):
+                context = Path(args[0][-1])
+                staged = context / "workspace"
+                self.assertTrue((staged / ".gitignore").is_file())
+                self.assertTrue((staged / ".dockerignore").is_file())
+                self.assertTrue((staged / ".env.example").is_file())
+                self.assertFalse((staged / ".git").exists())
+                return _ok()
+
+            with patch.object(
+                docker_mod.subprocess, "run", side_effect=inspect_context,
+            ):
+                docker_mod.build_image_with_cwd("derived:tag", "base:tag", workspace)
+
 
 if __name__ == "__main__":
     unittest.main()