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Stryker

Mutation testing for JavaScript and friends observed · 2026-08-28

github.com/stryker-mutator/stryker-js · homepage · TypeScript · Apache-2.0 (permissive) observed · 2026-08-28

Health v2 · maintenance only

95/100

  • Activity 99
  • Release rhythm 86
  • Longevity 100
How is this computed?

round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-03. Adoption (stars, forks) is never an input.

  • gap_med: 34
  • age_days: 3855
  • days_rel: 19
  • days_push: 7
  • n_releases_24m: 14

Full methodology

Adoption not part of the score

3050 stars · 278 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

Stryker is a mutation testing tool family that measures the effectiveness of your unit tests by automatically inserting bugs (mutants) into your source code and checking whether your tests catch them. It supports JavaScript/TypeScript (StrykerJS), .NET (Stryker.NET), and Scala (Stryker4s), with test-runner-agnostic execution and detailed HTML mutation reports.

Use cases

  • measure how effective my unit tests really are
  • find gaps in test coverage beyond code coverage metrics
  • run mutation testing on a TypeScript project
  • run mutation testing on a .NET Core project
  • generate a mutation score report in CI
  • find tests with missing assertions
  • improve test quality for a JavaScript codebase

When to choose

  • you want to evaluate test quality beyond line coverage
  • you work in JavaScript, TypeScript, C#, or Scala and want a mature, actively maintained mutation testing tool
  • you need test-runner-agnostic mutation testing with HTML reports
  • you want to catch surviving mutants that indicate weak or missing assertions

When to avoid

  • your test suite is slow, since mutation testing runs tests many times and can be very time-consuming
  • you need mutation testing for languages other than JavaScript/TypeScript, C#, or Scala
  • you only need simple code coverage metrics rather than test effectiveness analysis

Facets

cli-tool · maturity active

testing cli developer-tools testing developer-tools web-development cross-platform cli dotnet mutation-testing test-quality typescript javascript csharp scala test-runner-agnostic nodejs

9 sources

Member repositories

RepositoryRoleHealth v2
stryker-mutator/stryker-jsmain95
stryker-mutator/stryker-netsdk92

For agents

markdown · JSON · MCP: product_card(name="stryker-mutator/stryker-js")

Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem