The only one of those I have tried is tern, which didn't come close to IntelliJ's analysis, but obviously Javascript's a harder beast in this respect than Java,

The only one of those I have tried is tern, which didn't come close to IntelliJ's analysis, but obviously Javascript's a harder beast in this respect than Java, kotlin, Objective-C etc. > I wish, though, that half the development effort going into IDEs were instead directed towards better editor-agnostic tooling. In principle I agree. I like the thought of composable tools. But I wonder in practise. I'm trying to picture the vast array of facilities integrated in IntelliJ (analyses, many refactorings, syntax-aware snippets, amazing code navigation, structural search & replace, data flow anaylysis, syntax-aware select, omnipresent code generation, etc) integrated into a text editor via external tools. I suppose it could be done, but it seems unwieldy. And with how much work (setup and maintenance) on the part of the user? How often would things clash or need fixing? And with how much discoverability (a critical feature of IntelliJ)? What I do know is that working with code (not mere text!) in IntelliJ is quite a joy for me. For now, I'm glad someone has built it, even if the 'ultimate' composable set of tools might have some advantages.