Test-Driven Development — Iron Law
Strict TDD discipline: no production code without a failing test first — red-green-refactor with the iron law and a rationalization dismantler
- What
- Strict TDD discipline: no production code without a failing test first — red-green-refactor with the iron law and a rationalization dismantler
- Cost
- Free
- Needs
- a project where you can write and run tests (npm test / pytest / cargo test / go test ./... or equivalent).
- Install
- Copy the installer prompt below into your Muse — your agent does the rest.
Curated by Skill Harbor — an uncompromising TDD discipline skill built on the iron law: no production code without a failing test first — code written before the test gets deleted, not adapted. It enforces the full red-green-refactor cycle with mandatory failure verification (the test must fail for the right reason, not a typo), minimal green code (real behavior, no mocks unless unavoidable), a pristine verification step, and a refactor-only-after-green rule, plus good-test standards (one behavior, clear name, real code) and a table of "common rationalizations" that dismantles every excuse ("too simple to test", "I'll test after", "TDD will slow me down") with the reality check each one deserves. By @obra, listed here with credit to its creator. Honest caveats: it's deliberately dogmatic — it explicitly rejects the "spirit not ritual" reading, and even mandates running the project's full test suite rather than only the touched test file; the only exceptions (throwaway prototypes, generated code, config) require asking your human partner. Skill Harbor never reviews the code, review it yourself before use.
Version:
Install
Prerequisites: a project where you can write and run tests (npm test / pytest / cargo test / go test ./... or equivalent). Install "Test-Driven Development — Iron Law" for me. A strict TDD discipline: no production code without a failing test first, with the red-green-refactor cycle, good-test standards, and a rationalization dismantler. Repository: https://github.com/obra/superpowers/blob/main/skills/test-driven-development/SKILL.md 1. Fetch the SKILL.md file (and any helper files) from the repository path into a temporary folder and summarize what it does in one or two sentences. 2. Safety check: review the SKILL.md and scripts for anything suspicious (unexpected network calls, shell commands, credential harvesting). This repo should contain zero secrets in code, credentials only via the secure vault. Verify that holds here; STOP on any red flag and tell me. 3. Install it as a skill: copy SKILL.md and its helper files into the agent's skills directory, in a folder named "obra-test-driven-development". 4. Verify with no network calls: frontmatter valid, files in place. 5. Report what was installed, where, and what I still need to do myself. GitHub is optional: if I have a GitHub account or the gh CLI, you may use it; otherwise public access is fine. Never require it unless it's in the prerequisites above. Rules: don't touch anything outside the temp folder and the install target. If anything looks off, stop and ask me.
Questions
How do I install a build?
Every product page includes a copy-paste install prompt. Paste it into your Muse and it sets the build up for you — no manual configuration.
Where does my money go?
Straight to the seller. Skill Harbor never processes payments: checkout happens on the seller’s own page, usually Stripe.
What does the ✓ next to a creator’s name mean?
It means we confirmed the identity of the person behind the listing. It says nothing about the code itself — always check a build before installing it.