API, contract, BDD, web E2E, mobile, desktop, embedded and game testing, mutation and property-based testing, and unit tests per language.
API testing with Postman and Newman, REST Assured and Karate, plus Schemathesis and RESTler fuzzing and API tests run under injected network chaos. An authoring agent (api-test-author) picks the tool from observable project facts and writes one functional test per endpoint and scenario.
Behavior-driven development with Cucumber, Behave and Reqnroll: Gherkin from user stories and acceptance criteria, step libraries, and living docs. Converts stories, acceptance-criteria lists, manual steps or raw specs into Gherkin, keeps step definitions DRY, and covers SpecFlow-to-Reqnroll migration. Agents (bdd-scenario-author, gherkin-style-reviewer) write scenarios with step stubs and flag imperative steps and technical leakage.
Contract testing for microservices: Pact consumer and provider tests, OpenAPI, GraphQL and Protobuf breaking-change checks, and a combined deploy gate. The gate aggregates Pact can-i-deploy, oasdiff, graphql-inspector and buf breaking into one go / no-go verdict. Agents (contract-drift-investigator, contract-test-scaffolder) trace contract drift to its source and scaffold contract tests from a spec.
Desktop application testing for Windows (FlaUI, WinAppDriver), Electron (Playwright) and Qt (Qt Test), with a driver decision table. Also covers Linux AT-SPI, Spectron migration, and a test-review hazard checklist. An authoring agent (desktop-test-author) detects the driver, scaffolds a test project when none exists, and writes per-flow tests. macOS XCTest UI tests live in qa-mobile.
Embedded C/C++ testing: GoogleTest on ARM, Unity and Ceedling with CMock mocks, QEMU system emulation, gcov coverage, and hardware-in-the-loop. An authoring agent (embedded-test-author) detects the framework and execution path, scaffolds the harness when none exists, and writes one unit test per spec.
Game testing for Unity, Unreal and Godot: engine test frameworks, frame-time and memory profiling, gameplay record and replay, and multiplayer coverage. Includes the six-category game-test taxonomy and a platform certification overview (Sony TRC, Nintendo Lotcheck, Xbox Requirements, Steam Direct). An authoring agent (game-test-scenario-author) detects the engine, scaffolds the test tree, and writes one scenario per spec.
Mobile app testing: XCUITest and Espresso for native apps, Appium, Detox and Maestro across platforms, Flutter tests, and mobile accessibility checks. XCUITest also covers macOS desktop apps, and a tiered device matrix keeps CI cost down. An authoring agent (mobile-test-author) detects the driver, scaffolds a harness when none exists, and writes one test per spec. Mobile-web viewport emulation lives in qa-web-e2e.
Mutation testing with StrykerJS, Stryker.NET, PIT, mutmut and Mull: one canonical tool per language, plus triage of surviving mutants. Survivor triage classifies why each mutant lived (missing case, weak assertion, equivalent mutant) and drafts the tests that kill it.
Property-based testing with Hypothesis (Python), fast-check (JS/TS), proptest (Rust) and jqwik (JVM): generators, shrinking, and CI integration. Agents (property-based-test-author, vacuous-property-critic) write one property per invariant and flag assume-heavy or always-true properties.
Test-driven development for people and coding agents: red-green-refactor one test at a time, reproduce bugs with a failing test first, and prove a change works with test evidence before calling it done.
Go and Rust unit testing: table-driven Go tests with t.Run subtests, benchmarks, native fuzzing and the race detector, plus cargo test with Criterion. Each language skill covers framework choice and test conventions, with Ginkgo and Go mocking, rstest and mockall as references.
JavaScript and TypeScript unit testing with Jest and Vitest: configuration, mocking, coverage, CI, and choosing between the two. References cover Mocha maintenance, Jasmine-to-Jest migration, and deep coverage analysis. Test-code hygiene lives in qa-test-review.
JVM unit testing with JUnit 5: parameterized tests, lifecycle hooks, extensions, coverage and CI, plus framework choice for Java, Kotlin, Groovy and Scala. References cover Kotest, Spock, TestNG, ScalaTest and AssertJ.
.NET unit testing with xUnit.net: Fact and Theory tests, fixtures, parallel execution and CI, with NUnit, MSTest and FluentAssertions as references. Recommends xUnit for new projects, follows an existing NUnit or MSTest convention, and notes the FluentAssertions v8 license change.
Python unit testing with pytest: fixtures, parametrize, markers, mocking, coverage and CI, plus async tests with pytest-asyncio. Covers framework choice and test conventions, with unittest and doctest as references.
Web E2E testing with Playwright, Cypress, Selenium and WebdriverIO, plus cloud grids, a self-hosted Selenium Grid 4, and cross-browser test matrices. Covers BrowserStack, Sauce Labs and LambdaTest, traffic-based T1/T2/T3 browser tiers, a framework decision guide, and Playwright's agent tooling (playwright-cli, Playwright MCP, planner/generator/healer Test Agents). Agents (playwright-codegen-reviewer, automation-harness-bootstrapper) refactor recorded Playwright or Cypress Studio specs and scaffold a full E2E harness for a repo with no suite.
