EDIT: Actually it seems to be a library: https://github.com/jroimartin/gocui but the question still stands!
This was a pretty common technique in 90s DOS programs, but it can be tricky to get working cross platform over a serial terminal. The library you found seems to rely on termbox  for that.
 I thought Norton Commander did this, but I was mistaken - it just uses codepage 437. It was Norton Utilities .
My favorite DOS app that modified the VGA font was Impulse Tracker. It could actually draw oscilloscopes in text mode, and its source code is available.
And it would have come in really handy for studying for the google cloud support role I didn't get. Fault all my own.
wuzz seems to be focused on one request at a time, though.
The "written in X" is a very popular type of post for the HN audience because it usually points to source code like github/sourceforge. Your annoyance about it is puzzling and out of place. It's as if a commenter complains on a photography forum about a post titled "Paris Eiffel Tower taken with Canon 35mm lens"; the "Canon 35mm lens" is part of what makes the post interesting to potential readers of that particular community.
 50+ pages of results: https://hn.algolia.com/?query=written%20in&sort=byPopularity...
As sibling comment says, it's another angle for HN readers to be interested in. Someone might read it and think "meh, I like postman, I'm fine with that - oh but hey, Go, that's interesting - I like Go, I wonder how they..."
I can't understand how you are just noticing it now ?
Anyway I don't see a problem with it, like someone else mentioned, I might not be interested in yet another implementation of 'x' and would just scroll past it, however if it's implemented in a language I'm interested in then I might want to check out the code.
I like this interface personally because it separates the path to its own area, then headers and query parameters are separate areas with each instance on its own line.
It makes it quite easy to explore a rest interface and tweak your queries ad hoc.
Now, if only it would also support websockets. :p