Like a lot of good tools, Backstage started as a way to stop using a spreadsheet. They knew it was something worth open-sourcing when conference attendees paid more attention to the tool than the topics of the talks.
Backstage treats docs-like-code, keeping markdown files in the same repo as the code. Down with wikis, up with pull requests!
If you want to learn more about Backstage, check out our recent webinar with Emma Indal, a web engineer at Spotify.