mutation-testing
Validate test effectiveness with mutation testing using Stryker (TypeScript/JavaScript with Vitest or bun test via @hughescr/stryker-bun-runner) and mutmut (Python). Find weak tests that pass despite code mutations. Use to improve test quality.
89
87%
Does it follow best practices?
Impact
93%
1.43xAverage score across 3 eval scenarios
Passed
No known issues
Evaluation results
79%
16%Strengthen Test Suite with Mutation Testing
TypeScript Vitest stryker config
Correct vitest package
100%
100%
Core package installed
100%
100%
Config filename
100%
100%
testRunner vitest
100%
100%
packageManager bun
0%
0%
coverageAnalysis perTest
100%
100%
Correct thresholds
0%
50%
incremental enabled
0%
100%
mutate pattern
100%
100%
reporters configured
62%
100%
bunx stryker run
0%
0%
mutation-report.md created
100%
100%
100%
66%Add Mutation Testing to a Bun-Native Test Suite
Bun native test runner stryker config
Correct bun runner package
0%
100%
Core package version
0%
100%
Bun version requirement
0%
100%
Config filename
100%
100%
testRunner bun
100%
100%
coverageAnalysis perTest
100%
100%
Correct thresholds
0%
100%
incremental enabled
0%
100%
bun inspectorTimeout
0%
100%
mutate pattern
100%
100%
bunx stryker run command
0%
100%
100%
Improve Python Test Quality Using Mutation Testing
Python mutmut workflow and weak test improvement
mutmut install via uv
100%
100%
uv run mutmut run
100%
100%
uv run mutmut results
100%
100%
uv run mutmut show
100%
100%
No pip install mutmut
100%
100%
Exact value assertions
100%
100%
Boundary condition tests
100%
100%
Non-member below threshold
100%
100%
mutation-summary.md scores
100%
100%
workflow completeness
100%
100%
- Repository
- secondsky/claude-skills
- Commit
90d6bd7
- Evaluated
- Agent
- Claude Code
- Model
- Claude Sonnet 4.6
Table of Contents
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