Spec Kitty

Table of Contents

Spec Kitty is Spec Kitty, Inc.’s MIT-licensed Python CLI for spec-driven development that keeps specs, plans, work packages, review state, and merge decisions in your repository, and runs every work package in an isolated git worktree.

Spec Kitty is the first member of this category born as a company product around another member’s workflow: it started from Spec Kit, replaced the comprehensive-spec model with change-request deltas, and sells teams the governance and audit trail the free toolkits leave as conventions.

What it is
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A Python 3.11+ CLI (PyPI spec-kitty-cli, MIT, by Spec Kitty, Inc.) whose pipeline runs spec, plan, tasks, next, review, accept, merge, with mission artifacts under kitty-specs/ and work packages moving through lifecycle lanes (planned, in_progress, for_review, approved, done). Implementation happens in isolated git worktrees under .worktrees/, so parallel agents work without branch collisions, and review, accept, and merge are explicit gates with evidence attached. A governance layer keeps runtime decisions in the repo (spec-kitty advise, ask, and do map operator intent through a trail model), and every completed mission generates a retrospective by default. Slash commands or skills integrate Claude Code, Codex, Cursor, Gemini, Copilot, Windsurf, and OpenCode; the company sells demo-booked team platform access (TeamSpace, tracker sync) and training around the free CLI, and positions the whole thing as a governed software factory.

Status
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Active, company-backed, and mid-adoption. As of 2026-10-06: 1,668 stars and 177 forks since creation on 2025-10-09, pushed 2026-10-06, MIT, stable PyPI release 3.2.7 (2026-09-09) and 3,251 PyPI downloads last month, with a 4.x release-candidate line in qualification (v4.0.0rc5, 2026-10-02) whose README says stable launch acceptance remains pending. The repository moved from its original Priivacy-ai org to the spec-kitty org, which GitHub’s redirect confirmed this run. Its Hacker News footprint is one 5-point thread (January 2026), so its adoption case rests on stars, installs, and the company’s own surfaces, not on independent discussion. Creator Robert Douglass presented the workflow at FrOSCon 2026 on 2026-08-16.

Strengths
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Per-work-package git worktree isolation is a first-class feature here, not a pattern you assemble yourself, and no other column runs implementation this way by default.
Review, accept, and merge are stateful gates with attached evidence, the strongest convergence machinery in this category alongside AI-DLC’s audit trail.
Specs are change requests describing the delta and code stays the source of truth, the same delta insight OpenSpec is built on.
The founder’s own comparison concedes the boundary plainly: if one developer at one keyboard is your problem, use Spec Kit.

Cautions
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The company gravity is structural: the CLI is free, but TeamSpace, tracker sync, and training are the paid surface, the same pattern Tessl runs at larger scale.
The 4.x line is a prerelease and PyPI shows a yanked 4.1.5 (uploaded 2026-04-15), so pin 3.2.7 until the stable launch lands.
Adoption sits an order of magnitude under the category leaders, 3.3k PyPI downloads a month against OpenSpec’s 2.45M npm downloads.
Independent coverage is one third-party review (Hysenlabs, 2026-09-10) and that 5-point thread, so the claims rest on the project’s own documentation and blog.
The positioning wanders across its own surfaces (governed software factory, delivery control plane, doctrine-driven delivery), and the vocabulary churn this category keeps producing is already visible.

Pricing
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The CLI is free and open source under MIT. The company sells demo-booked team platform access and training; no tiers are published as of 2026-10-06.

Compared to
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GitHub Spec Kit: the upstream Spec Kitty broke from; Spec Kit scaffolds markdown conventions for one developer-agent pair, Spec Kitty adds lanes, worktrees, gates, and governance for teams.
OpenSpec: the other delta-spec member; OpenSpec archives a ledger with no company attached, Spec Kitty wraps the delta model in execution state and a vendor.
GSD: the other loop with isolation; GSD quarantines context in fresh subagents per phase, Spec Kitty isolates per work package in git worktrees with human review gates.

Bottom line
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Recommended for teams past the one-agent stage that want parallel implementation, review gates, and an auditable record, and that accept a company product sitting on their repo’s spec state. Not for solo work (its own docs call it overkill), and not for anyone who needs the 4.x line before its stable launch. The disagreeable claim I will defend: two members reaching delta specs from opposite directions, OpenSpec by design and Spec Kitty by breaking from Spec Kit, is evidence that the comprehensive-spec model at Spec Kit’s root is the part of this movement that will not survive, while the governance plumbing both added is the part that will.