Discord and Pinterest use Elixir at a massive scale. Discord in particular has been writing a great technical blog about the process.
On a smaller scale Feedback Panda very successfully bootstrapped to a 55k MRR SaaS and was aquired in under 2 years: https://youtu.be/vaXp81OxxK0
Edit: Not to be too self-promotional, but AFIK I've created more free Elixir-learning screencasts than anyone on YouTube. I cover a pretty broad range of topics from total beginner to some fairly niche things: https://youtu.be/z1nKbzZiRtY
On a smaller scale Feedback Panda very successfully bootstrapped to a 55k MRR SaaS and was aquired in under 2 years: https://youtu.be/vaXp81OxxK0
Edit: Not to be too self-promotional, but AFIK I've created more free Elixir-learning screencasts than anyone on YouTube. I cover a pretty broad range of topics from total beginner to some fairly niche things: https://youtu.be/z1nKbzZiRtY