Technical Summary
A Technical Case Study on Zero-Overhead Mocking for Native AOT
Abstract
The transition to Cloud-Native architecture demands runtimes that are instant, lightweight, and efficient. Microsoft's Native AOT compilation delivers this, offering Go-like startup speeds for C# applications. However, enterprise adoption is stalled by a legacy dependency: Reflection.
Skugga proposes shifting mocking from Runtime to Compile-Time using C# 12 Interceptors. Results demonstrate a 5.1x improvement in CPU efficiency, a 4x reduction in deployment footprint, and linear build scalability.
Computational Efficiency
| Metric | Standard JIT | Skugga AOT | Improvement |
|---|---|---|---|
| User CPU Time | 0.36s | 0.07s | 5.1x More Efficient |
| System CPU Time | 0.18s | 0.12s | 33% Less Overhead |
| Total Work | 0.54s | 0.19s | 2.8x Faster Completion |
High-throughput microservices achieve 5x higher packing density in Kubernetes clusters.
Deployment Footprint
| Metric | Standard JIT | Skugga AOT | Improvement |
|---|---|---|---|
| Artifact Size | ~200 MB | 47 MB | 4x Smaller |
| Attack Surface | Full Linux OS | Scratch (No OS) | Maximal Security |
76% reduction in artifact size improves Mean Time To Recovery (MTTR) during auto-scaling events.
Scalability
Stress test with 500 distinct mocks:
- Build Time: 0.41 seconds
- Test Execution: 0.49 seconds (~1ms per test)
The Roslyn Incremental Generator pipeline ensures negligible build overhead at scale.
Conclusion
Skugga removes the runtime overhead of mocking, unlocking:
- Instant Startup (<50ms)
- Minimal Footprint (47MB)
- Maximum Efficiency (5.1x CPU gain)