write-failing-test-first
Before fixing any bug, write a test that reproduces it and watch it fail. Use for every bug fix.
Source facts
- Repository
- Archive228/loopkit
- Last source activity
- June 29, 2026 at 21:52
- Detected SKILL.md language
- English
- Stars
- 757
- Forks
- 124
Install options
The review-first prompt is selected by default. You can switch to a direct command or download a local copy.
Review the source files
Read SKILL.md and any companion files shown by SkillsMP before deciding whether to install.
Showing SKILL.md
SKILL.md
Source instructions · Read-only preview- name
- write-failing-test-first
- description
- Before fixing any bug, write a test that reproduces it and watch it fail. Use for every bug fix.
- when_to_use
- fixing a bug, "make X work", a reported defect
# Write the Failing Test First
The only proof you fixed a bug is a test that failed before and passes after.
1. Write the smallest test that reproduces the reported behavior.
2. Run it. **Watch it fail** for the right reason (read the assertion, not just red).
3. Now fix the code.
4. Run the test. It passes. Run the FULL suite — you didn't break anything else.
If you can't write the test easily, the architecture is telling you something (tight coupling). Say so.
Never: fix first, test after (you'll write a test that passes regardless). Never: skip the watch-it-fail step.
View on GitHub