That's quite nice. There is a small risk that the client request mechanism might change . The headers don't change much - mostly when a new platform gets added. Go is only targeting amd64 and arm64.

This isn't so much about leaks. The most important thing that this will enable is correct analysis of uninitialised memory. Without annotation memory that gets recycled will not be correctly poisoned. I imagine that it will also be useful for the other tools (except cachegrind and callgrind).