ck
NewThree commands, one SPEC.md, caveman encoding, bug-to-spec backprop
Overview
<h1 align="center">cavekit</h1>
<p align="center"> <strong>compressed spec-driven development for claude code</strong><br/> <sub>one file · three commands · zero sub-agents</sub> </p>
what this is
Plan-then-execute forgets. SDD remembers — but most SDD frameworks bury that value under agent swarms, dashboards, and ceremony that costs more tokens than it saves.
Cavekit 4 is a rewrite from the ground up. It keeps only what earns its place:
- •durable spec —
SPEC.mdat repo root survives context resets. - •caveman encoding — ~75% fewer tokens than prose. Symbols, fragments,
pipe tables for repeating records.
- •backprop reflex — every test failure becomes a
§Bentry; classes
of bug become §V invariants the spec never forgets.
That's the whole pitch.
commands
| cmd | job |
|---|---|
/ck:spec | create / amend / backprop SPEC.md. Sole mutator. |
/ck:build | native plan → execute against spec. Auto-backprops on failure. |
/ck:check | read-only drift report. Lists §V / §I / §T violations. |
install
One line, via the skills CLI:
npx skills add JuliusBrussee/cavekitInstalls five skills into ~/.claude/skills/: spec, build, check (the workflow) plus caveman and backprop (the utilities). Claude activates each when its trigger context matches — e.g. "write a spec for…" invokes spec, "build the next task" invokes build. Claude Code picks them up on next launch.
Or via the Claude Code marketplace (also adds /ck:spec, /ck:build, /ck:check slash commands):
/plugin marketplace add juliusbrussee/cavekit
/plugin install ck@cavekitOr clone directly:
git clone https://github.com/juliusbrussee/cavekit.git ~/.claude/plugins/cavekitformat
See `FORMAT.md`. Fixed sections: §G goal, §C constraints, §I interfaces, §V invariants, §T tasks (pipe table), §B bugs (pipe table).
files
FORMAT.md spec schema + caveman encoding rules
commands/ three slash-command entry points (/ck:spec, /ck:build, /ck:check)
skills/spec spec mutator (mirrors commands/spec.md as a skill)
skills/build plan-execute skill (mirrors commands/build.md)
skills/check drift report skill (mirrors commands/check.md)
skills/caveman encoding utility
skills/backprop bug → spec protocol (six steps)non-goals
- •no sub-agents. Main Claude does the work.
- •no dashboards.
cat SPEC.mdis the dashboard. - •no parallel workers. One thread, one spec, one diff.
- •no JSON / YAML spec bodies. Markdown + pipe tables.
- •no hooks, no orchestration binaries, no TypeScript helpers.
older cavekit (the Hunt lifecycle, v3.1.0 and earlier)
The previous generation is not deprecated — it is frozen at tag `v3.1.0` and remains a fully working plugin.
What it is:
Spec-driven AI development with an autonomous execution loop. Four-command
Hunt lifecycle (
/ck:sketch→/ck:map→/ck:make→/ck:check),plus
/ck:ship,/ck:review,/ck:revise,/ck:status,/ck:design,
/ck:research,/ck:init,/ck:config,/ck:resume,/ck:help— 16slash commands total. 12 named sub-agents. Per-task token budgets,
stop-hook state machine, model-tier routing, auto-backpropagation from
test failures, tool-result caching, Codex peer review, Karpathy
behavioral guardrails, caveman token compression, knowledge-graph
integration, and design-system enforcement. Parallel wave execution and
team mode.
Pick v3.1.0 if you want the full autonomous loop, parallel agents, peer review, or design-system workflow. Pick v4 if you want the distilled core — one spec, three commands, no orchestration.
install the older version
Marketplace:
/plugin marketplace add juliusbrussee/[email protected]
/plugin install ck@cavekitGit:
git clone -b v3.1.0 https://github.com/juliusbrussee/cavekit.gitFull docs live at the tag — git checkout v3.1.0 and read the README there for command reference, skill catalog, and the Hunt lifecycle guide.
choosing, or moving
See `UPGRADE.md`. Honest framing:
- •Stay on v3.1.0 if your project has active
context/kits/investment. - •Move to v4 if you want fewer moving parts and smaller token bills.
- •It is a two-way door —
SPEC.mdis plain markdown; nothing traps
you in either direction.
ecosystem
Cavekit is one rock in the caveman family:
| repo | what |
|---|---|
| caveman | output compression skill — why use many token when few do trick |
| cavemem | cross-agent persistent memory — why agent forget when agent can remember |
| cavekit (you here) | spec-driven build loop — why agent guess when agent can know |
| cavegemma | Gemma 4 31B fine-tuned on caveman pairs — why prompt every turn when weight remember |
philosophy
The spec is the only artifact that earns its tokens. Everything else
that costs tokens must either save more tokens later, or the user's
attention, or it gets cut.
See `CHANGELOG.md` for the full v3 → v4 break.
license
MIT.
Install & Usage
mkdir -p .claude/skillsmkdir -p .claude/skills && curl -o .claude/skills/ck.md https://raw.githubusercontent.com/JuliusBrussee/cavekit/main/SKILL.md/ckFrequently Asked Questions
What is ck?
Three commands, one SPEC.md, caveman encoding, bug-to-spec backprop
How to install ck?
To install ck, create the .claude/skills directory in your project, then run the curl command to download the skill file. Once installed, invoke it in Claude Code with /ck.
What is ck best for?
ck is a community categorized under Development. Created by Julius Brussee.