If you want performance, you need to refactor your code into a small performance-critical unsafe core (that has higher test coverage and audit standards), while

If you want performance, you need to refactor your code into a small performance-critical unsafe core (that has higher test coverage and audit standards), while keeping the rest of the business logic in the safe domain, and relying on the CLR to do the heavy lifting and guarantee memory consistency. Bonus point: you can write the core in C++ and use COM-like marshaling for absolutely unbeatable performance (no actual COM runtime is needed).