Render supports building / deploying docker containers so it supports everything, including Java.
render.com and fly.io are in a similar niche of "deploy your app easily".
To me fly.io prioritized the wrong thing: deploying apps close to users. I care more about low price, ease of use and features than optimizing latency.
render.com is the best (that I know) "run a server for your app" service. I used Digital Ocean vps and then apps before.
If you don't care about optimizing latency, we definitely didn't build Fly.io for you. That's not because you want the wrong thing, though. It's because we have a narrow and, we think, very valuable focus.
We're actually not in the same niche as Render! At least, I'm pretty sure we're building towards different things. But we are each (a) small (b) scrapping with large public cloud providers and (c) attempting to generate a self sustaining startup reaction.
Attracting people with new apps is a way both of us prove the value of what we're doing. Attracting people who want to run their apps close to their users is the way we make a lot of money.
* How does it different than new "lightweight" cloud offering like Fly.io?