We ended up rewriting NuGet Restore in .NET 9

a year ago

NuGet Restore algorithm was rewritten to improve performance and scalability, reducing restore times significantly.
Initial optimizations cut restore times in half, but a full rewrite achieved a 16x improvement (from ~32 mins to ~2 mins).
The new algorithm avoids recursion and duplicate nodes, reducing memory usage and improving efficiency.
Collaboration across NuGet, Visual Studio, and .NET teams was key to the project's success.
The rewrite involved extensive testing, including automated tests, real-life repository tests, and dogfooding.
Performance improvements led to significant cost savings and productivity gains for large repositories.
Future work includes addressing known regressions, adding more parallelism, and enabling the new resolver for lock files.
Key learnings: performance unlocks value, fresh perspectives help, and robust testing is essential.

Hasty Briefsbeta