No, each request is handled concurrently in the same thread using evented IO. You spawn fibers, which are the analogue to go's goroutines, and many of those run

No, each request is handled concurrently in the same thread using evented IO. You spawn fibers, which are the analogue to go's goroutines, and many of those run in one thread. Just like nodejs (without callbacks/promises/async/await) and similar to go with GOMAXPROCS=1. Unfortunately, I don't have a timeframe for parallelism, it's not my area of crystal and it's a fairly tricky issue. My (biased, i'm a core developer) view on Crystal's maturity, after using it in a few of my own side-projects, is that once crystal code compiles, it runs pretty much rock solid in production. Compiler bugs are fairly rare too, although the compiler clearly isn't as mature as gcc. The main issue you face is lack of available libraries, and being forced to make a few changes every couple months when a new release comes out with breaking changes. Depending on the size of your codebase, that could be a big issue or it could be a 5 minute easy commit.