Thanks for your work, this really looks promising!
One question I keep thinking about. What if I want to still use React on the frontend, does it still make sense to use Phoenix for the backend then or am I throwing all benefits over board then?
Phoenix is still fantastic for JSON and GraphQL apis. In fact, with GraphQL subscriptions, it's extremely well suited because how well we handle WebSockets and pubsub. The community has a robust GraphQL toolkit which works with Phoenix. It has long been 1.0 and has had a book published around it, so quite solid:
http://absinthe-graphql.org
One question I keep thinking about. What if I want to still use React on the frontend, does it still make sense to use Phoenix for the backend then or am I throwing all benefits over board then?