So, once upon a time I wanted to associate information with http connections (as I am accustomed to in every other language I've ever written) just to enable proper http keepalive and debugging through a proxy written in Go.
Ended up with this. [0]
Turns out the Go authors don't think you should do this so I had to majorly alter and recompile the stdlib.
I still appreciate many go tools and the cross platform single binaries that work great on Solaris/Illumos. But in many cases the strong opinions of Go authors really stand in the way of getting work done.