Install & build

System requirements

DotSlash

The GitHub Release also contains a DotSlash file for the Codex CLI named codex. Using a DotSlash file makes it possible to make a lightweight commit to source control to ensure all contributors use the same version of an executable, regardless of what platform they use for development.

Build from source

# Clone the repository and navigate to the root of the Cargo workspace.
git clone https://github.com/openai/codex.git
cd codex/codex-rs

# Install the Rust toolchain, if necessary.
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
source "$HOME/.cargo/env"
rustup component add rustfmt
rustup component add clippy

# Build Codex.
cargo build

# Launch the TUI with a sample prompt.
cargo run --bin codex -- "explain this codebase to me"

# After making changes, ensure the code is clean.
cargo fmt -- --config imports_granularity=Item
cargo clippy --tests

# Run the tests.
cargo test