Introduction

Fairlead keeps a coding agent on course in your repository. It enforces your project’s rules at the moment the agent acts, gives it only the context that applies to the files in front of it, runs only the tests a change can reach, keeps project memory small, and measures whether all of that is working.

It is a single Rust binary with no project-specific logic: everything about your repository lives in your own fairlead.toml.

This book documents Fairlead 0.12.0, the latest release. The book for an earlier release is its docs/ folder at that release’s tag, such as v0.5.1.

It covers installing Fairlead and its configuration; the import graph it builds without an install, with coverage maps for what imports can’t show; the test plan and how to run it in CI, with the run’s report and the escapes the default branch finds; the guard rules and the hooks that run them as an agent works; the change loop an agent follows: the brief before an edit, the done gate before it’s finished, and the receipt after; and replay, which measures the plan against real CI failures, with the benchmarks that come from it. The roadmap says what comes next.