Go’s generics aren’t boxed. At least, not in the sense that Java’s are. For example, you can write generic functions that operate over slices of unboxed values.
Still worse than true monomorphized generics in C# which too has fast compilation times (by nature of being JIT-compiled, but AOT target is still faster than Rust once you download dependencies).
Go’s implementation strategy for generics essentially is monomophirization plus obvious code size optimizations (e.g. don’t generate different code for different pointer types given that they all have the same underlying representation). Do you have specific scenario in mind where Go’s implementation strategy carries a significant performance penalty? I think possibly there are some misconceptions in this thread about how Go’s implementation actually works.
