Skugga vs Others

A comprehensive comparison of Skugga against other .NET mocking frameworks.

At a Glance

Feature	Skugga	Moq	NSubstitute	FakeItEasy
Native AOT	Yes	No	No	No
Zero Reflection	Yes	No	No	No
Compile-Time	Yes	No	No	No
Familiar API	Yes (Moq-compat)	N/A	Different	Different
Chaos Engineering	Yes	No	No	No
OpenAPI Mocking	Yes	No	No	No
Zero-Alloc Testing	Yes	No	No	No
Self-Writing Tests	Yes	No	No	No

Performance

Comprehensive benchmarks across 12 scenarios (50,000 iterations each):

Framework	Speed vs Skugga	Notes
Skugga	Baseline	Compile-time, zero reflection
Moq	2.6-80x slower	80x slower on argument matching
NSubstitute	3.5x slower	Consistent but reflection-heavy
FakeItEasy	3.9x slower	Similar overhead across scenarios

Key Findings

• Overall: Skugga is 6.36x faster than Moq
• Argument Matching: 79.84x faster
• Void Method Setup: 59.26x faster
• Callback Execution: 53.34x faster
• Mock Creation: 15.29x faster

Real-World Impact

For a test suite with 10,000 tests using argument matchers:

• Skugga: 2.7 seconds
• Moq: 218 seconds
• Saved: 215 seconds per test run

Why is Skugga Faster?

Legacy libraries use System.Reflection.Emit to generate proxy classes at runtime. This incurs heavy CPU penalties and forces the JIT compiler to work overtime.

Skugga does all heavy lifting at compile-time:

• Zero JIT Penalties -- Code is already compiled to native machine code
• Zero Reflection -- No Expression.Lambda().Compile() or MethodInfo lookups
• Zero Dynamic Allocation -- No Castle.DynamicProxy or similar
• Optimized Dispatch -- Simple dictionary lookups instead of reflection