The Go vs JavaScript lineup is quite stunning. Go destroys Node.js in memory usage and performance on every test except regex-redux (edge case?). http://benchmarksgame.alioth.debian.org/u64q/compare.php?lan...
It looks like the JS version is using the built in runtime's regex engine.
I don't know exactly why (maybe differences or missing features in go's regex) but the go version is actually using the c FFI to call pcre.h, and without profiling it I'd guess a huge hit is that alone.