RSpec vs JUnit 5

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

JUnit Team · since 2017

• 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.

• Universal support across IDEs, build tools and CI in the Java ecosystem.
• The extension model replaced JUnit 4's runners and rules with something composable.
• Pairs cleanly with Mockito, AssertJ, Spring Test and Testcontainers.

• 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.

• Java verbosity persists — expect more lines per test than in Python or JavaScript.
• Parallel execution is opt-in and still occasionally surprising.
• Mixed JUnit 4 and 5 codebases need the vintage engine and stay confusing for years.

Ruby and Rails applications.

Every Java and Kotlin project on the JVM.