core-agent-ide/codex-rs
zbarsky-openai 2a06d64bc9
feat: add support for building with Bazel (#8875)
This PR configures Codex CLI so it can be built with
[Bazel](https://bazel.build) in addition to Cargo. The `.bazelrc`
includes configuration so that remote builds can be done using
[BuildBuddy](https://www.buildbuddy.io).

If you are familiar with Bazel, things should work as you expect, e.g.,
run `bazel test //... --keep-going` to run all the tests in the repo,
but we have also added some new aliases in the `justfile` for
convenience:

- `just bazel-test` to run tests locally
- `just bazel-remote-test` to run tests remotely (currently, the remote
build is for x86_64 Linux regardless of your host platform). Note we are
currently seeing the following test failures in the remote build, so we
still need to figure out what is happening here:

```
failures:
    suite::compact::manual_compact_twice_preserves_latest_user_messages
    suite::compact_resume_fork::compact_resume_after_second_compaction_preserves_history
    suite::compact_resume_fork::compact_resume_and_fork_preserve_model_history_view
```

- `just build-for-release` to build release binaries for all
platforms/architectures remotely

To setup remote execution:
- [Create a buildbuddy account](https://app.buildbuddy.io/) (OpenAI
employees should also request org access at
https://openai.buildbuddy.io/join/ with their `@openai.com` email
address.)
- [Copy your API key](https://app.buildbuddy.io/docs/setup/) to
`~/.bazelrc` (add the line `build
--remote_header=x-buildbuddy-api-key=YOUR_KEY`)
- Use `--config=remote` in your `bazel` invocations (or add `common
--config=remote` to your `~/.bazelrc`, or use the `just` commands)

## CI

In terms of CI, this PR introduces `.github/workflows/bazel.yml`, which
uses Bazel to run the tests _locally_ on Mac and Linux GitHub runners
(we are working on supporting Windows, but that is not ready yet). Note
that the failures we are seeing in `just bazel-remote-test` do not occur
on these GitHub CI jobs, so everything in `.github/workflows/bazel.yml`
is green right now.

The `bazel.yml` uses extra config in `.github/workflows/ci.bazelrc` so
that macOS CI jobs build _remotely_ on Linux hosts (using the
`docker://docker.io/mbolin491/codex-bazel` Docker image declared in the
root `BUILD.bazel`) using cross-compilation to build the macOS
artifacts. Then these artifacts are downloaded locally to GitHub's macOS
runner so the tests can be executed natively. This is the relevant
config that enables this:

```
common:macos --config=remote
common:macos --strategy=remote
common:macos --strategy=TestRunner=darwin-sandbox,local
```

Because of the remote caching benefits we get from BuildBuddy, these new
CI jobs can be extremely fast! For example, consider these two jobs that
ran all the tests on Linux x86_64:

- Bazel 1m37s
https://github.com/openai/codex/actions/runs/20861063212/job/59940545209?pr=8875
- Cargo 9m20s
https://github.com/openai/codex/actions/runs/20861063192/job/59940559592?pr=8875

For now, we will continue to run both the Bazel and Cargo jobs for PRs,
but once we add support for Windows and running Clippy, we should be
able to cutover to using Bazel exclusively for PRs, which should still
speed things up considerably. We will probably continue to run the Cargo
jobs post-merge for commits that land on `main` as a sanity check.

Release builds will also continue to be done by Cargo for now.

Earlier attempt at this PR: https://github.com/openai/codex/pull/8832
Earlier attempt to add support for Buck2, now abandoned:
https://github.com/openai/codex/pull/8504

---------

Co-authored-by: David Zbarsky <dzbarsky@gmail.com>
Co-authored-by: Michael Bolin <mbolin@openai.com>
2026-01-09 11:09:43 -08:00
..
.cargo chore(ci): add cargo audit workflow and policy (#7108) 2025-11-24 12:20:55 -08:00
.config fix flaky test: approval_matrix_covers_all_modes (#7028) 2025-11-20 14:37:42 -08:00
.github/workflows chore(ci): add cargo audit workflow and policy (#7108) 2025-11-24 12:20:55 -08:00
ansi-escape feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
app-server feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
app-server-protocol feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
app-server-test-client feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
apply-patch feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
arg0 feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
async-utils feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
backend-client feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
chatgpt feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
cli feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
cloud-tasks feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
cloud-tasks-client feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
codex-api feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
codex-backend-openapi-models feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
codex-client feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
common feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
core feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
debug-client chore: add small debug client (#8894) 2026-01-08 13:40:14 +00:00
docs feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
exec feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
exec-server feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
execpolicy feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
execpolicy-legacy feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
feedback feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
file-search feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
keyring-store feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
linux-sandbox feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
lmstudio feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
login feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
mcp-server feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
mcp-types feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
ollama feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
otel feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
process-hardening feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
protocol feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
responses-api-proxy feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
rmcp-client feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
scripts remove release script (#7885) 2025-12-11 13:40:48 -08:00
stdio-to-uds feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
tui feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
tui2 feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
utils feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
windows-sandbox-rs feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
.gitignore [MCP] Prefix MCP tools names with mcp__ (#5309) 2025-10-19 20:41:55 -04:00
BUILD.bazel feat: add support for building with Bazel (#8875) 2026-01-09 11:09:43 -08:00
Cargo.lock fix: remove existing process hardening from Codex CLI (#8951) 2026-01-08 21:19:34 -08:00
Cargo.toml fix: leverage codex_utils_cargo_bin() in codex-rs/core/tests/suite (#8887) 2026-01-08 14:56:16 +00:00
clippy.toml fix: switch rate limit reset handling to timestamps (#5304) 2025-10-17 17:39:37 -07:00
code Send text parameter for non-gpt-5 models (#4195) 2025-09-24 22:00:06 +00:00
config.md Fix link to MCP Servers config section (#5301) 2025-10-17 14:58:27 -07:00
default.nix fix: drop stale filedescriptor output hash for nix (#7865) 2025-12-11 10:43:50 -08:00
deny.toml fix: upgrade lru crate to 0.16.3 (#8845) 2026-01-07 10:11:27 -08:00
README.md chore: update outdated docs (#8701) 2026-01-03 02:19:52 -08:00
rust-toolchain.toml chore: upgrade to Rust 1.90 (#4124) 2025-09-24 08:32:00 -07:00
rustfmt.toml Update cargo to 2024 edition (#842) 2025-05-07 08:37:48 -07:00

Codex CLI (Rust Implementation)

We provide Codex CLI as a standalone, native executable to ensure a zero-dependency install.

Installing Codex

Today, the easiest way to install Codex is via npm:

npm i -g @openai/codex
codex

You can also install via Homebrew (brew install --cask codex) or download a platform-specific release directly from our GitHub Releases.

Documentation quickstart

What's new in the Rust CLI

The Rust implementation is now the maintained Codex CLI and serves as the default experience. It includes a number of features that the legacy TypeScript CLI never supported.

Config

Codex supports a rich set of configuration options. Note that the Rust CLI uses config.toml instead of config.json. See docs/config.md for details.

Model Context Protocol Support

MCP client

Codex CLI functions as an MCP client that allows the Codex CLI and IDE extension to connect to MCP servers on startup. See the configuration documentation for details.

MCP server (experimental)

Codex can be launched as an MCP server by running codex mcp-server. This allows other MCP clients to use Codex as a tool for another agent.

Use the @modelcontextprotocol/inspector to try it out:

npx @modelcontextprotocol/inspector codex mcp-server

Use codex mcp to add/list/get/remove MCP server launchers defined in config.toml, and codex mcp-server to run the MCP server directly.

Notifications

You can enable notifications by configuring a script that is run whenever the agent finishes a turn. The notify documentation includes a detailed example that explains how to get desktop notifications via terminal-notifier on macOS. When Codex detects that it is running under WSL 2 inside Windows Terminal (WT_SESSION is set), the TUI automatically falls back to native Windows toast notifications so approval prompts and completed turns surface even though Windows Terminal does not implement OSC 9.

codex exec to run Codex programmatically/non-interactively

To run Codex non-interactively, run codex exec PROMPT (you can also pass the prompt via stdin) and Codex will work on your task until it decides that it is done and exits. Output is printed to the terminal directly. You can set the RUST_LOG environment variable to see more about what's going on.

Experimenting with the Codex Sandbox

To test to see what happens when a command is run under the sandbox provided by Codex, we provide the following subcommands in Codex CLI:

# macOS
codex sandbox macos [--full-auto] [--log-denials] [COMMAND]...

# Linux
codex sandbox linux [--full-auto] [COMMAND]...

# Windows
codex sandbox windows [--full-auto] [COMMAND]...

# Legacy aliases
codex debug seatbelt [--full-auto] [--log-denials] [COMMAND]...
codex debug landlock [--full-auto] [COMMAND]...

Selecting a sandbox policy via --sandbox

The Rust CLI exposes a dedicated --sandbox (-s) flag that lets you pick the sandbox policy without having to reach for the generic -c/--config option:

# Run Codex with the default, read-only sandbox
codex --sandbox read-only

# Allow the agent to write within the current workspace while still blocking network access
codex --sandbox workspace-write

# Danger! Disable sandboxing entirely (only do this if you are already running in a container or other isolated env)
codex --sandbox danger-full-access

The same setting can be persisted in ~/.codex/config.toml via the top-level sandbox_mode = "MODE" key, e.g. sandbox_mode = "workspace-write".

Code Organization

This folder is the root of a Cargo workspace. It contains quite a bit of experimental code, but here are the key crates:

  • core/ contains the business logic for Codex. Ultimately, we hope this to be a library crate that is generally useful for building other Rust/native applications that use Codex.
  • exec/ "headless" CLI for use in automation.
  • tui/ CLI that launches a fullscreen TUI built with Ratatui.
  • cli/ CLI multitool that provides the aforementioned CLIs via subcommands.