Read on Twitter
Psalm’s language server is truly open-source, but it needs much more work to be able to compete with paid offerings. The problem with language servers is they’re hard to code, hard to test and debug, and usually require the underlying parser to support malformed code. (1/5) https://twitter.com/marcelpociot/status/1349775036979290114
The type of engineer who’s able to battle those challenges normally doesn’t spend their time writing PHP, which removes the hobbyist incentive — “I made this because I needed it in my day-to-day work”. (2/5)
But there’s an obvious demand — most engineers love error detection and autocompletion in their IDE, which means there’s a commercial incentive for companies like JetBrains to build those offerings. (3/5)
Thankfully the non-language-server bits of Psalm are very simple to test, and not too difficult to debug (if you have a bit of existing domain knowledge), and it benefits massively from being open-source. (4/5)
And indeed Psalm is a healthy open-source project! The most recent release is (I think) the first where the majority of activity hasn’t come from me, and I’m working to make it more maintainable still. (Fin)
