So far most of the datacenters are built in very convenient places and people will start to build them in inconvenient places like Sahara or Mongolia way before they will building them in space
Building nuclear-powered and solar powered datacenters in places with low population density will still be cheaper. Do you think Mongolian government won't allow China to build datacenters if the price is right?
Twitter's back-end is written in Scala, but they used "better Java" style so an average developer should have no problems making changes
Anyway, what kind of features Twitter (or any social network for that matter) needs after it existed for so many years? Hacker News haven't changed a bit a it does what it does perfectly well
It was the default method of contacting the dealers on Russian darknet when everything was a just a message board (hell, it was available without TOR) and not a proper marketplace