diff --git a/.codex/config.toml b/.codex/config.toml
new file mode 100644
index 0000000..d4af786
--- /dev/null
+++ b/.codex/config.toml
@@ -0,0 +1,5 @@
+sandbox_mode = "workspace-write"
+approval_policy = "on-request"
+
+[sandbox_workspace_write]
+network_access = true
diff --git a/.codex/environments/environment.toml b/.codex/environments/environment.toml
new file mode 100644
index 0000000..e5b38a8
--- /dev/null
+++ b/.codex/environments/environment.toml
@@ -0,0 +1,48 @@
+# THIS IS AUTOGENERATED. DO NOT EDIT MANUALLY
+version = 1
+name = "ctrlsys"
+
+[setup]
+script = '''
+cd "$CODEX_WORKTREE_PATH"
+uv venv .venv --python 3.11
+uv pip install --python .venv/bin/python ".[test,dev]"
+uv pip install --python .venv/bin/python .
+'''
+
+[cleanup]
+script = '''
+rm -rf .pytest_cache .mesonpy-* build build-* dist *.egg-info
+find . -type d -name __pycache__ -prune -exec rm -rf {} +
+'''
+
+[[actions]]
+name = "Rebuild"
+icon = "tool"
+command = "uv pip install ."
+
+[[actions]]
+name = "Smoke pytest"
+icon = "test"
+command = ".venv/bin/pytest tests/python/test_mb04ts.py -v"
+
+[[actions]]
+name = "Full pytest"
+icon = "test"
+command = ".venv/bin/pytest tests/python/ -n auto"
+
+[[actions]]
+name = "Translation checks"
+icon = "test"
+command = '''
+scripts/check_translation_coverage.py --report-only
+scripts/check_translation_smells.py
+'''
+
+[[actions]]
+name = "ASAN Docker"
+icon = "debug"
+command = '''
+docker build --platform linux/arm64 -t slicot-asan -f docker/Dockerfile.asan docker/
+./scripts/run_asan_docker.sh --no-build
+'''