Thanks for wanting to make gstack better. Whether you're fixing a typo in a skill prompt or building an entirely new workflow, this guide will get you up and running fast.
gstack skills are Markdown files that Claude Code discovers from a skills/ directory. Normally they live at ~/.claude/skills/gstack/ (your global install). But when you're developing gstack itself, you want Claude Code to use the skills in your working tree — so edits take effect instantly without copying or deploying anything.
That's what dev mode does. It symlinks your repo into the local .claude/skills/ directory so Claude Code reads skills straight from your checkout.
git clone <repo> && cd gstack
bun install # install dependencies
bin/dev-setup # activate dev mode
Now edit any SKILL.md, invoke it in Claude Code (e.g. /review), and see your changes live. When you're done developing:
bin/dev-teardown # deactivate — back to your global install
bin/dev-setup creates a .claude/skills/ directory inside the repo (gitignored) and fills it with symlinks pointing back to your working tree. Claude Code sees the local skills/ first, so your edits win over the global install.
gstack/ <- your working tree
├── .claude/skills/ <- created by dev-setup (gitignored)
│ ├── gstack -> ../../ <- symlink back to repo root
│ ├── review -> gstack/review
│ ├── ship -> gstack/ship
│ └── ... <- one symlink per skill
├── review/
│ └── SKILL.md <- edit this, test with /review
├── ship/
│ └── SKILL.md
├── browse/
│ ├── src/ <- TypeScript source
│ └── dist/ <- compiled binary (gitignored)
└── ...
# 1. Enter dev mode
bin/dev-setup
# 2. Edit a skill
vim review/SKILL.md
# 3. Test it in Claude Code — changes are live
# > /review
# 4. Editing browse source? Rebuild the binary
bun run build
# 5. Done for the day? Tear down
bin/dev-teardown
# 1. Copy .env.example and add your API key
cp .env.example .env
# Edit .env → set ANTHROPIC_API_KEY=sk-ant-...
# 2. Install deps (if you haven't already)
bun install
Bun auto-loads .env — no extra config. Conductor workspaces inherit .env from the main worktree automatically (see "Conductor workspaces" below).
| Tier | Command | Cost | What it tests |
|---|---|---|---|
| 1 — Static | bun test |
Free | Command validation, snapshot flags, SKILL.md correctness, TODOS-format.md refs, observability unit tests |
| 2 — E2E | bun run test:e2e |
~$3.85 | Full skill execution via claude -p subprocess |
| 3 — LLM eval | bun run test:evals |
~$0.15 standalone | LLM-as-judge scoring of generated SKILL.md docs |
| 2+3 | bun run test:evals |
~$4 combined | E2E + LLM-as-judge (runs both) |
bun test # Tier 1 only (runs on every commit, <5s)
bun run test:e2e # Tier 2: E2E only (needs EVALS=1, can't run inside Claude Code)
bun run test:evals # Tier 2 + 3 combined (~$4/run)
Runs automatically with bun test. No API keys needed.
test/skill-parser.test.ts) — Extracts every $B command from SKILL.md bash code blocks and validates against the command registry in browse/src/commands.ts. Catches typos, removed commands, and invalid snapshot flags.test/skill-validation.test.ts) — Validates that SKILL.md files reference only real commands and flags, and that command descriptions meet quality thresholds.test/gen-skill-docs.test.ts) — Tests the template system: verifies placeholders resolve correctly, output includes value hints for flags (e.g. -d <N> not just -d), enriched descriptions for key commands (e.g. is lists valid states, press lists key examples).claude -p (~$3.85/run)Spawns claude -p as a subprocess with --output-format stream-json --verbose, streams NDJSON for real-time progress, and scans for browse errors. This is the closest thing to "does this skill actually work end-to-end?"
# Must run from a plain terminal — can't nest inside Claude Code or Conductor
EVALS=1 bun test test/skill-e2e.test.ts
EVALS=1 env var (prevents accidental expensive runs)claude -p can't nest)[Ns] turn T tool #C: Name(...)test/skill-e2e.test.ts, runner logic in test/helpers/session-runner.tsWhen E2E tests run, they produce machine-readable artifacts in ~/.gstack-dev/:
| Artifact | Path | Purpose |
|---|---|---|
| Heartbeat | e2e-live.json |
Current test status (updated per tool call) |
| Partial results | evals/_partial-e2e.json |
Completed tests (survives kills) |
| Progress log | e2e-runs/{runId}/progress.log |
Append-only text log |
| NDJSON transcripts | e2e-runs/{runId}/{test}.ndjson |
Raw claude -p output per test |
| Failure JSON | e2e-runs/{runId}/{test}-failure.json |
Diagnostic data on failure |
Live dashboard: Run bun run eval:watch in a second terminal to see a live dashboard showing completed tests, the currently running test, and cost. Use --tail to also show the last 10 lines of progress.log.
Eval history tools:
bun run eval:list # list all eval runs (turns, duration, cost per run)
bun run eval:compare # compare two runs — shows per-test deltas + Takeaway commentary
bun run eval:summary # aggregate stats + per-test efficiency averages across runs
Eval comparison commentary: eval:compare generates natural-language Takeaway sections interpreting what changed between runs — flagging regressions, noting improvements, calling out efficiency gains (fewer turns, faster, cheaper), and producing an overall summary. This is driven by generateCommentary() in eval-store.ts.
Artifacts are never cleaned up — they accumulate in ~/.gstack-dev/ for post-mortem debugging and trend analysis.
Uses Claude Sonnet to score generated SKILL.md docs on three dimensions:
Each dimension is scored 1-5. Threshold: every dimension must score ≥ 4. There's also a regression test that compares generated docs against the hand-maintained baseline from origin/main — generated must score equal or higher.
# Needs ANTHROPIC_API_KEY in .env — included in bun run test:evals
claude-sonnet-4-6 for scoring stabilitytest/skill-llm-eval.test.tsclaude -p), so it works from anywhere including inside Claude CodeA GitHub Action (.github/workflows/skill-docs.yml) runs bun run gen:skill-docs --dry-run on every push and PR. If the generated SKILL.md files differ from what's committed, CI fails. This catches stale docs before they merge.
Tests run against the browse binary directly — they don't require dev mode.
SKILL.md files are generated from .tmpl templates. Don't edit the .md directly — your changes will be overwritten on the next build.
# 1. Edit the template
vim SKILL.md.tmpl # or browse/SKILL.md.tmpl
# 2. Regenerate
bun run gen:skill-docs
# 3. Check health
bun run skill:check
# Or use watch mode — auto-regenerates on save
bun run dev:skill
To add a browse command, add it to browse/src/commands.ts. To add a snapshot flag, add it to SNAPSHOT_FLAGS in browse/src/snapshot.ts. Then rebuild.
If you're using Conductor to run multiple Claude Code sessions in parallel, conductor.json wires up workspace lifecycle automatically:
| Hook | Script | What it does |
|---|---|---|
setup |
bin/dev-setup |
Copies .env from main worktree, installs deps, symlinks skills |
archive |
bin/dev-teardown |
Removes skill symlinks, cleans up .claude/ directory |
When Conductor creates a new workspace, bin/dev-setup runs automatically. It detects the main worktree (via git worktree list), copies your .env so API keys carry over, and sets up dev mode — no manual steps needed.
First-time setup: Put your ANTHROPIC_API_KEY in .env in the main repo (see .env.example). Every Conductor workspace inherits it automatically.
.tmpl template, not the .md. Run bun run gen:skill-docs to regenerate./ship auto-detects completed items. All planning/review/retro skills read it for context.browse/src/*.ts, run bun run build.~/.claude/skills/gstack. bin/dev-teardown restores the global one.bin/dev-setup runs automatically via conductor.json..env propagates across worktrees. Set it once in the main repo, all Conductor workspaces get it..claude/skills/ is gitignored. The symlinks never get committed.When you're developing gstack in one workspace and want to test your branch in a different project (e.g. testing browse changes against your real app), there are two cases depending on how gstack is installed in that project.
.claude/skills/gstack/ in the project)Point your global install at the branch:
cd ~/.claude/skills/gstack
git fetch origin
git checkout origin/<branch> # e.g. origin/v0.3.2
bun install # in case deps changed
bun run build # rebuild the binary
Now open Claude Code in the other project — it picks up skills from
~/.claude/skills/ automatically. To go back to main when you're done:
cd ~/.claude/skills/gstack
git checkout main && git pull
bun run build
.claude/skills/gstack/ checked into the project)Some projects vendor gstack by copying it into the repo (no .git inside the
copy). Project-local skills take priority over global, so you need to update
the vendored copy too. This is a three-step process:
Update your global install to the branch (so you have the source):
cd ~/.claude/skills/gstack
git fetch origin
git checkout origin/<branch> # e.g. origin/v0.3.2
bun install && bun run build
Replace the vendored copy in the other project:
cd /path/to/other-project
# Remove old skill symlinks and vendored copy
for s in browse plan-ceo-review plan-eng-review review ship retro qa setup-browser-cookies; do
rm -f .claude/skills/$s
done
rm -rf .claude/skills/gstack
# Copy from global install (strips .git so it stays vendored)
cp -Rf ~/.claude/skills/gstack .claude/skills/gstack
rm -rf .claude/skills/gstack/.git
# Rebuild binary and re-create skill symlinks
cd .claude/skills/gstack && ./setup
Test your changes — open Claude Code in that project and use the skills.
To revert to main later, repeat steps 1-2 with git checkout main && git pull
instead of git checkout origin/<branch>.
When you're happy with your skill edits:
/ship
This runs tests, reviews the diff, triages Greptile comments (with 2-tier escalation), manages TODOS.md, bumps the version, and opens a PR. See ship/SKILL.md for the full workflow.