Install

Install the CLI

Both binaries — act, the host, and act-build, the component post-processor — ship as prebuilt binaries on npm and PyPI, and as source on crates.io. The npm and PyPI packages carry the same binary; pick whichever ecosystem you already have.

npx (no install)

npx @actcore/act --help
npx @actcore/act-build --help

Good for a one-off run. Caches to ~/.npm/_npx/.

uvx (no install)

uvx --from act-cli act --help
uvx --from act-build act-build --help

The package is act-cli, the command it installs is act — hence --from.

npm global

npm install -g @actcore/act @actcore/act-build

Installs act and act-build on $PATH.

pip / uv

uv tool install act-cli
uv tool install act-build
# or: pip install act-cli act-build

Platform wheels for macOS (x86_64, arm64) and Linux (x86_64, aarch64, riscv64; glibc and musl). No Python is involved at run time — the wheel is just a delivery vehicle for the binary.

The glibc wheels require glibc 2.34 or newer (Debian 12, Ubuntu 22.04, RHEL 9); the riscv64 wheel requires 2.39. On an older distribution, install the musl build — or use npm, whose packages ship musl binaries and carry no floor.

cargo

cargo install act-cli act-build

Compiles from source. Requires a recent stable Rust.

Docker

docker pull ghcr.io/actcore/act:latest
docker run --rm ghcr.io/actcore/act --help

Verify

act --version
act --help

act --version reports whichever release you just installed — the current one is on the releases page.

act --help should list the subcommands run, call, info, skill, pull, session, store, inspect, secret, and login.

To build components

You need a Rust or Python toolchain depending on which SDK you use.

Rust

rustup toolchain install nightly
rustup target add wasm32-wasip2 --toolchain nightly

Components pin the toolchain with rust-toolchain.toml; you don’t need +nightly flags day-to-day.

Python

curl -LsSf https://astral.sh/uv/install.sh | sh

The act-sdk Python package runs inside componentize-py at build time; uv manages the dev environment.

Next

• Run your first component — pull a published component and call it in three commands.
• Build your own — Rust or Python scaffold.