"weird stack structure necessary to enable goroutines also impedes FFI performance" is probably the greater part of that equation. Keeping parameters straight

"weird stack structure necessary to enable goroutines also impedes FFI performance" is probably the greater part of that equation. Keeping parameters straight between Cgo and Go is another fine kick in the nuts. That's true with almost every FFI of course, but with FFI from Python to C, there's usually a little performance boost to make up for the pain. Go however, is fast enough to begin with. FFI is all pain there.