RSpec vs Vitest

Free and open source

Free and open source

Free and open source. You pay in engineering time and CI minutes.

Free and open source. You pay in engineering time and CI minutes.

Everything, self-hosted

Everything, self-hosted

Widely used

RSpec Team · since 2005

Category standard

VoidZero / OSS community · since 2021

• The output reads as documentation of intended behaviour.
• Shared examples and contexts keep large Rails suites organised.
• Deep integration with the Rails ecosystem — Capybara, FactoryBot, VCR.

• Fastest watch-mode feedback of the JavaScript runners, by a wide margin on large repos.
• Zero-config ESM and TypeScript — the single biggest source of Jest configuration pain simply disappears.
• Jest-compatible API means migration is usually a day, not a quarter.

• Deeply nested contexts with let and before hooks become very hard to follow.
• The DSL is a language of its own to learn.
• Rails suites tend towards slowness; expect to invest in parallelisation.

• Assumes Vite. On a Webpack or Metro project the advantage largely evaporates.
• Younger ecosystem; a handful of niche Jest plugins have no equivalent.
• Browser mode is still maturing relative to a dedicated component test runner.

Ruby and Rails applications.

Any Vite-based project, and most new JavaScript projects generally.