Module engine 

Engine — the core orchestration loop.

The engine is the central coordinator. It owns the tick loop, backend connections, channel registry, transport layer, and tmux session manager.

Submodules handle the heavy lifting:

• tick — core tick phases (session polling, stuck recovery, routing, dispatch)
• sync — periodic sync operations (cleanup, PR review, mentions, skills)
• review — PR review pipeline (review agent, auto-merge, change handling)
• cleanup — worktree cleanup and merged-PR detection

This file contains struct definitions, project initialization, and the main event loop (serve()).

Modules

auto_merge

PR auto-merge and review-changes handling.

channel_handler

Channel message handlers — routes incoming channel messages to the appropriate action.

cleanup

Worktree cleanup and merged-PR detection.

commands

Owner slash commands — parse, validate, and execute /commands in issue comments.

cooldown

Per-agent and per-model cooldown tracking.

dependencies

Sync GitHub blocked-by links into SQLite and hold tasks until those links are done.

dispatch_guard

RAII guard for the per-task dispatching DashMap.

events

Task event bus — broadcast channel for status transitions.

jobs

Job scheduler — replaces jobs_tick.sh.

priority

relay

Client for orch-relay, which receives the GitHub App’s webhooks on Cloudflare. orch connects out, so it needs no endpoint. The contract is PROTOCOL.md in the orch-relay repository

review

PR review pipeline — review agent orchestration.

review_gate

The CI gate before a review: a review starts only once CI has run on the PR head

review_poll

PR review polling — review_open_prs.

review_shipcheck

Runs shipcheck before a review that has no CI result, so the reviewer’s shipcheck run returns the stored result instead of starting the suite inside the review’s time limit (#3943)

router

Agent router — selects the best agent and model for each task.

runner

Task runner — executes tasks using AI agents.

subscribers

suspend

Host suspend/resume detection.

sync

Sync tick — periodic operations that run less frequently than the core tick.

tasks

tick

Core tick loop phases.

Structs

EngineConfig

Engine configuration.

ProjectEngine

Per-project engine state.

RunTimeouts

The limit the timeout wrapper puts on one agent run, per complexity

Constants

RATE_LIMITED_UNTIL_KEY

KV key holding the epoch second the GitHub core window resets, so orch task status can show the limit from a separate process.

RUN_TIMEOUT_GRACE_SECS

Seconds a live session may run past its own timeout before stuck recovery takes it. The timeout wrapper ends the agent at the limit, and the runner still collects the result

Functions

attribution_footer

Build a standard attribution footer for GitHub comments posted by orch bots.

configured_agents

Return the configured agent list from top-level agents in config.yml, falling back to router::config::DEFAULT_AGENTS when not set.

format_rate_limited_until

Format an epoch second as a local HH:MM:SS for operator-facing output.

orch_footer

Standard Orch attribution footer for issue bodies, PR bodies, and comments.

serve

Start the orch service.