NUnit vs RSpec

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

.NET Foundation · since 2002

Widely used

RSpec Team · since 2005

• The most expressive built-in assertion library in .NET.
• Familiar attribute model for teams migrating from older frameworks.
• Very stable, very long-lived.

• 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.

• Shared test-class instances mean state can leak between tests unless you are careful.
• New Microsoft templates default to xUnit, so it is drifting from the mainstream.
• Attribute-heavy style feels dated.

• 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.

Existing .NET codebases already standardised on NUnit.

Ruby and Rails applications.