Docs

Introduction

Last Light is a self-hostable, MIT-licensed AI coding agent for GitHub. It sits in front of one or more repositories, listens for events, and runs an AI agent against them to triage issues, review pull requests, respond to comments, and — when you ask — build features end-to-end through an Architect → Executor → Reviewer cycle. It runs on your own infrastructure, under your own model keys — no SaaS in the loop.

It is built on agentic-pi — it runs on any model the pi coding agent supports (Claude, GPT, Gemini, Llama, and more; default anthropic/claude-sonnet-4-6) with a lightweight TypeScript harness that handles webhook ingestion, Slack messaging, cron scheduling, sandbox isolation, and an admin dashboard. Every piece of non-trivial behavior is expressed as a YAML workflow — the harness itself knows nothing about "build" or "triage" specifically; it just executes the phases a workflow declares.

What it does out of the box

  • Triages new issues — labels, deduplicates, chases missing info.
  • Reviews pull requests — posts severity-ranked feedback with file:line references.
  • Builds features on request — Architect plans, Executor implements, Reviewer verifies, fix-feedback loops, PR opened.
  • Writes weekly health reports — open/stale issues, PR velocity, action items.
  • Talks to you on Slack — per-thread conversation, DB-backed session history.
  • Gives you a dashboard — live activity, pipeline DAGs, full session drill-down.

Who it's for

Last Light is for teams and individuals who want an AI coding agent they fully own — from solo maintainers keeping libraries and side projects healthy, to enterprises that need every issue, review, and build to run inside their own perimeter. Self-hosted, MIT-licensed, and always on: it keeps working for you after dark.

It runs as a single container you deploy somewhere you control. There is no SaaS — you own the webhook endpoint, the Docker volume, and the audit trail.

How this documentation is organized

  • Quick start with Claude is the fastest path — install the bundled Claude Code skills and let Claude stand the whole stack up for you.
  • Getting Started walks you through prerequisites, creating a GitHub App, running locally, deploying to production, and wiring up Slack — the by-hand route.
  • Reference documents every environment variable the harness reads.
Want the architecture story first? Read How it works for the narrative on EventEnvelope, the YAML workflow engine, phases, execution modes, permission profiles, and approval gates.