Install and update M3

Install the M3 CLI and the project SDK separately. The CLI runs m3 and includes the local results viewer. The SDK runs inside the Python project being tested.

Requirements

M3 supports Python 3.10 and newer. The commands below use uv. The alternative shell installer supports macOS and Linux and requires curl plus either Python 3 or uv.

Install the CLI

Install the standalone command once for your user with uv:

uv tool install sf-m3-cli

The CLI runs outside your project environment. To update it, use:

uv tool upgrade sf-m3-cli

On macOS or Linux, you can use the shell installer instead:

curl -LsSf https://m3.sineframe.com/install.sh | sh

The installer selects the latest stable GitHub release, verifies its release installer and checksums, and installs the CLI in isolated tool storage. It uses uv when available and otherwise creates a dedicated virtual environment. To update an installation made this way, rerun the same command.

Install the project SDK

From a project directory, initialize M3 and prepare its Python environment:

m3 init
m3 setup
m3 doctor

m3 init creates the project identity and a skipped pytest starter. Replace that starter with a real assertion before relying on test results. m3 setup installs the SDK release matching the CLI, with pytest, storage, and judge support, into the selected project environment. It does not install the CLI in that environment or edit dependency manifests and lockfiles. m3 doctor checks the CLI and project environment separately.

Keep the CLI and project SDK on matching releases. If the environment is recreated or synchronized, run m3 setup again. For a project that manages its dependencies directly, add sf-m3[pytest] as a project dependency instead of using CLI-managed setup; you still install the standalone CLI separately when you want m3 test, saved history, or the bundled viewer.

With uv, add the SDK from the project root with:

uv add "sf-m3[pytest]"

This declares the SDK in the project manifest. The standalone CLI remains a separate user-level installation.

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