Ask HN: Is there any apps out there built using single lang for the whole stack? 9 years ago
Maybe not today (reasonbably). But, until recently there were many apps (and still possibly many are) using Django (python) and Ruby on Rails (Ruby) as their development stack for web apps. Atleast for Ruby on Rails, I know of some popular apps that were built using it like Airbnb, Github, Spotify, Twitch, Soundcloud etc.