Pure Test vs Testem

Pure Test is a free, minimal test runner for projects using JavaScript runtimes and browsers. It supports Node.js, Deno, Bun, Cloudflare Workers, and browsers, and its API includes test suites, assertions, lifecycle hooks, spies, fake timers, and retry and timeout options. The CLI provides multiple reporters, test filters, file watching, sharding, and fail-fast execution. For CI, `--shard` splits test files across jobs and exits cleanly when a shard has no files. TypeScript test discovery requires `--ts` on Node.js; it is automatic on Deno and Bun. A Deno adapter registers tests as `Deno.test()` calls for use with `deno test` and its filtering and IDE workflows. The README includes migration guides for Jest and Vitest and notes compatibility with common mock methods. Pure Test does not isolate tests, so lifecycle hooks are recommended for managing state. The project is beta, and its APIs may change. It is Apache-2.0 licensed, with no paid plans stated.

Testem is a JavaScript test runner for running tests in Node.js, real desktop browsers, or a launcher you configure. It supports Jasmine, QUnit, Mocha, and custom framework adapters, and can be used for unit, integration, end-to-end-style, or custom test setups. Browser runs can use Chrome, Firefox, Safari, or Edge, including a Headless Chrome launcher. In development mode, a terminal interface watches project files and reruns tests after relevant changes; CI mode can run tests in available browsers in parallel. Testem includes CI reporters for TAP, dot, xunit, and TeamCity, with custom reporters available. Listed preprocessing support includes Babel, TypeScript, Browserify, ESLint, JSHint, JSLint, and CoffeeScript. Its API provides startDev, startCI, and startServer modes, and coverage reporting is supported. It works with GitHub Actions, Jenkins, and TeamCity. Testem is free and open source under the MIT license, and runs on Linux, macOS, and Windows. It requires a supported Node.js runtime: ^22.17.0, ^24.0.0, or >=26.0.0.