Where to go to find Edinburgh's arts and theatre underbelly? There must be...something?

Ironically, given the Edinburgh Festival, I'm struggling to find a 'fringe' theatre scene in Edinburgh. If anyone reading this has ever lived in Manchester or London of NY or even places like Bristol or Leeds and Huddersfield you'll know that a pretty thriving little fringe arts scene exists. I'm not talking amdram – I'm thinking more like new writing, fringe nights, testing out new plays or pieces of writing for the stage.

I know the Traverse exists. I love it. But programming is super infrequent and that's more of an end point for plays. What about all the stuff that gets to the traverse (for example)?

Am I missing something? I know Edinburgh isn't London, and I love her for it – but I'm homesick for the theatre scene there because it strikes me as odd that a city that hosts something like Edinburgh Festival can't have this undercurrent of creativity.

I'm the sort of person who will start something if it doesn't exist, so if anyone knows of any scratch nights or local theatre makers before I crack on and create something, I would LOVE LOVE LOVE to hear from you.

This post is shared out of genuine curiosity and confusion rather than criticism. I think it's me and I'm looking in the wrong places so please enlighten me!!