Few years back Eclipse with ScalaIDE plugin was the tool of choice for Scala developers. Nowadays Metals (LSP server for Scala) is 2nd most important IDE solution in Scala Ecosystem and its user base is growing quickly and steadily. I was involved in building ScalaIDE (e.g. I was main author of the expression evaluator in its debugger) and now my team is driving development for Metals and Eclipse Kotlin Plugin (so I am still in touch with Eclipse platform).
During this talk I want to compare how ScalaIDE and Metals approach the same problems and highlight strengths and weaknesses of an aspect-based integration with JDT and lightweight solution based on LSP protocol. Hopefully
I will be able to convince you that such a protocol-based solution is a future despite its limitations.