xUnit.net vs Mocha

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

Category standard

.NET Foundation · since 2007

Widely used

OpenJS Foundation · since 2011

• Per-test instance isolation eliminates a whole class of shared-state bugs by design.
• Idiomatic modern C# — no attribute soup.
• The default in current .NET project templates.

• Small, stable and predictable — it does one job and has done it the same way for years.
• Pick your own assertions, mocks and coverage rather than accepting a bundle.
• Excellent async and reporter support.

• Fewer built-in assertions than NUnit; most teams add FluentAssertions.
• The isolation model surprises developers migrating from NUnit.
• Parallelism defaults occasionally bite on integration tests.

• No built-in mocking, snapshots, coverage or parallel-by-default execution.
• Assembling and documenting the stack is work every new project repeats.
• Fewer new projects adopt it; momentum sits with Vitest and Jest.

New .NET projects.

Node.js services where you want explicit control over every part of the test stack.