ef30e59860
tests/io.test.cjs's "review fix: pending-outcome cell lifetime" describe block deliberately drives runMain()/output() in-process (needed to observe a cross-invocation state leak) instead of via a subprocess. output() ends with a raw synchronous fs.writeSync(1, ...) to the real stdout fd, and Node's --test-isolation=process (default since Node 22) uses that same fd for the file's own parent-child reporter protocol. The two writes racing produced an intermittent "Unable to deserialize cloned data" that killed the whole file — observed twice on next's macOS lane, most recently on the commit that merged PR #4428 (unrelated to that PR's content; io.test.cjs isn't part of its diff). Empirically validated locally (gsd-test can't reach macOS): built a repro loop running N parallel copies of `node --test tests/io.test.cjs` to recreate CI-like contention. Baseline: ~13-17% of runs hit the corruption (12/90, 15/90 across two samples). A first fix attempt wrapped the writes in captureFdAsync (an await-aware twin of the existing captureFdSync, added because runMain() defers main() through a microtask chain, so a synchronous wrap restores before the real write fires) — but captureFdAsync always forwards to the real fs.writeSync by design (matching captureFdSync's "never swallow" contract, tests/helpers.cjs, #4306). Re-ran the same loop against that fix: 15/90, statistically unchanged. Forwarding the write doesn't stop it from reaching the fd node:test's own IPC also uses. Replaced it with suppressFdAsync: a narrow, deliberate exception to the never-swallow contract for a window the caller has verified is fully controlled (a single runMain() call plus its promise-chain settling, where nothing else can legitimately need that fd). It records the bytes for the test's own assertions but never lets them reach the real fd. Re-ran the loop: 0/300 across three samples (90+120+90), including one round at 8-way parallelism. Also caught and fixed a real bug surfaced by the same loop: the new regression assertion checked for compact-JSON `"error":"x"` but output() pretty-prints, so it failed 100% of runs deterministically until fixed to parse and check the structured value instead (io.test.cjs, matching this repo's "assert on structured output, not raw text" convention). Co-authored-by: sim <sim@local> Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
GSD Core
Git. Ship. Done.
English · Português · 简体中文 · 日本語 · 한국어
A light-weight meta-prompting, context engineering, and spec-driven development system for Claude Code, OpenCode, Antigravity CLI, Kimi CLI, Kilo, Codex, Copilot, Cursor, Windsurf, and more.
What is GSD Core
GSD Core is a context-engineering and spec-driven development framework that drives AI coding agents (Claude Code, Codex, Antigravity CLI, Kimi CLI, Copilot, Cursor, and more) through a disciplined phase loop. It solves context rot — the quality degradation that accumulates as an AI fills its context window — by running all heavy research, planning, and execution work in fresh-context subagents while keeping your main session lean.
How it works
Each milestone repeats the same five-step loop, one phase at a time:
- Discuss — capture implementation decisions before anything is planned
- Plan — research, decompose, and verify the plan fits a fresh context window
- Execute — run plans in parallel waves; each executor starts with a clean 200k-token context
- Verify — walk through what was built; diagnose and fix before declaring done
- Ship — create the PR, archive the phase, repeat for the next one
Quickstart
npx @opengsd/gsd-core@latest
The installer prompts for your runtime (Claude Code, OpenCode, Antigravity CLI, Kimi CLI, Kilo, Codex, Copilot, Cursor, Windsurf, and more) and whether to install globally or locally. The installer is required for cross-runtime compatibility — do not copy files from agents/ or commands/ directly.
On another runtime or without Node.js? See Install on your runtime.
Once installed, start a new project or onboard an existing repo:
/gsd-new-project # greenfield project
/gsd-onboard # existing codebase
New here? Follow Your first project for a guided walkthrough from install to first shipped phase, or Onboarding an existing codebase for brownfield setup.
Documentation
What's new in 1.7.0 → docs/whats-new-1.7.0.md
Tutorials — learning by doing:
How-to guides — task-focused recipes:
Reference — authoritative facts:
Explanation — concepts and design decisions:
Full index: docs/README.md. Other languages: 日本語 · 한국어 · Português · 简体中文.
Why it works
Most AI-coding setups fail at scale because context bloat silently degrades output quality, there is no shared memory between sessions, and nothing verifies that code actually works. GSD Core solves all three: heavy work runs in fresh subagents, structured artifacts like STATE.md and CONTEXT.md survive session boundaries, and the verify step walks through what was built and generates fix plans before a phase is declared done. See docs/explanation/context-engineering.md for the full reasoning.
Troubleshooting? See docs/how-to/recover-and-troubleshoot.md.
Community
| Project | Platform |
|---|---|
| gsd-opencode | Original OpenCode port |
| Discord | Community support |
Star History
License
MIT License. See LICENSE for details.
Claude Code is powerful. GSD Core makes it reliable.