22 articles
Master unit testing in TypeScript with Vitest. Covers setup, writing tests, mocking modules and dependencies, spies, coverage, and testing Express route handlers and services.
Comprehensive comparison of Jest and Vitest in 2026 — performance benchmarks, TypeScript support, migration guide, and which framework to choose for Node.js and TypeScript projects.
Write production-grade API integration tests with Supertest and Vitest. Covers HTTP assertions, authentication headers, database seeding, test isolation, and CI pipeline setup for Node.js Express APIs.
AI tools accelerate test-driven development by generating test cases, implementing code to pass them, and suggesting edge cases humans miss. This guide shows how to integrate AI into a real TDD workflow with Python and JavaScript examples.
Vitest and React Testing Library together form the modern testing stack for React applications. This guide covers setup, writing component tests, user interaction testing, mocking API calls, and best practices for maintainable test suites.
Complete testing guide for 2026 using Vitest for unit tests, React Testing Library for component tests, and Playwright for E2E tests. Includes CI configuration and coverage strategies.
Master agent evaluation: trajectory analysis, tool accuracy, task completion rates, efficiency scoring, and LLM-as-judge evaluation frameworks.
Build code generation agents that parse specs, generate code with examples, validate syntax, run tests, and iterate until code passes.
Build automated evaluation pipelines with LLM-as-judge, DeepEval metrics, and RAGAS to catch quality regressions before users see them.
Test AI systems with mocking, snapshot testing, property-based testing, and regression suites.
Implement consumer-driven contract testing with Pact to verify that APIs and clients agree on their interface without full integration tests.
Test migrations for backwards compatibility, forwards compatibility, rollback safety, and data integrity. Catch schema-code mismatches before deployment.
Master Helm chart design with sensible defaults, comprehensive testing, and promotion pipelines. Scale from single-chart deployments to Helmfile-orchestrated multi-chart platforms.
Implement hexagonal architecture to keep your domain logic framework-agnostic and testable, with ports defining contracts and adapters providing implementations.
Test Terraform modules with Terratest, enforce policies with OPA/Conftest, scan with tfsec, and catch infrastructure bugs in CI before deployment.
Treat prompts as code with version control, A/B testing, regression testing, and multi-environment promotion pipelines to maintain quality and prevent prompt degradation.
Node.js 18+ includes a native test runner. Learn how node:test replaces Jest and Vitest with zero dependencies, built-in mocking, and sub-second test runs.
Move beyond Jest mocks. Use Vitest for ESM support and speed, TestContainers for real databases, MSW for HTTP mocking, and contract testing with Pact for production confidence.
Comprehensive penetration testing checklist: IDOR, authentication bypass, rate limiting, XXE, SSRF, mass assignment, GraphQL introspection, API fuzzing, and ZAP integration.
Manage prompts with version control, automated regression testing, eval datasets, A/B testing in production, and canary deployments for safe prompt evolution.
Master the RAGAS framework and build evaluation pipelines that measure faithfulness, context relevance, and answer quality without expensive human annotation.
Use TestContainers to run real PostgreSQL, Redis, and Kafka in tests. Isolate data per test, parallelize safely, and catch integration bugs before production.