The local, zero-cost merge queue for parallel Claude Code agents serializes landings so push races, redundant heavy builds, and shared-resource test flakiness can't happen. The author pushes up to 90 commits a day on a MacBook Air with 8GB RAM via 4-5 parallel agents, avoiding CI minute costs.

Install via `npm install --save-dev claude-code-merge-queue` and initialize with `npx claude-code-merge-queue init`. Configuration lives in one file with auto-detected integration branch and check command. Unlike GitHub's Merge Queue (Enterprise Cloud only, billed Actions minutes), this runs locally on any plan for $0.

Commands include `hook worktree-create`, `build-lock`, `land` (FIFO queue), `sync`, `promote` (human-only), `preview`, `port`, and `prune`. A pre-push hook enforces `land` and runs `check Command` before allowing pushes. Emergency hatch via `CLAUDE_CODE_MERGE_QUEUE_EMERGENCY_PUSH=1` bypasses blocks.

Limits: no human reviews, single-machine FIFO queue in local temp storage, crash-safe locks by PID liveness, rebase conflicts abort cleanly. MIT licensed.