Question about Expert support

[flavioescobar]

Just wanted to ask if this plugin intends to support the Expert LSP, or if the community should consider building a separate plugin specifically for this.

If you look at Expert's installation guide you'll see that multiple editors support it. It would be awesome if we had support for IntelliJ IDEs as well.

I would love to help with this myself, but I don't think I have the skillset.

[joshuataylor]

Unfortunately IntelliJ plugins rely heavily on PSI and other Jetbrains-specific functionality (such as syntax highlighting, SDK support, etc).

This would be amazing to support, and something we'll look into ASAP, but there is this MASSIVE caveat...

The integration with the Language Server Protocol is created as an extension to the commercial IntelliJ-based IDEs. Therefore, plugins using Language Server integration are not available in JetBrains products like IntelliJ IDEA Community Edition and Android Studio from Google.

https://plugins.jetbrains.com/docs/intellij/language-server-protocol.html#supported-ides

[gaggle]

Yeah, much as I like JetBrain in general this is one area where it looks like they're protecting their own castle instead of opening up what would bring value to a lot of users.

Nonetheless my humble opinion is the future of Elixir in JetBrains is better severed by delegating as much as possible to Expert (well, LSPs) to always have a guaranteed minimum experience that matches other editors, and lower the cost of ongoing maintenance. But it should be acknowledged that if this project chooses that, then it is a decision that will come at the cost of all free users. Not an easy choice, I imagine.

@flavioescobar I also don't have the skillset (i.e. Java knowledge), but I do occasionally wonder what it'd be like to jump into it. I wonder how much ChatGPT can help make (or totally ruin) a from-scratch plugin lol! 😂

[joshuataylor]

It's much easier now than before, but the problem with the plugin (and other plugins) is that JetBrains has deprecated a bunch of APIs, and made better checking for threading, which is good, but it has broken a lot of their internal plugins as well...

Would love to enhance as much as possible with LSP, a fair chunk of users tend to use RubyMine (paid), IntelliJ Ultimate (paid).

[flavioescobar]

@joshuataylor Thank for clarifying this! It's really unfortunate that we can't do this for the free IDEs for now.

But in terms of the paid IDEs, does this mean we would need a separate plugin in this case?

[angelozerr]

I suggest that you try LSP4IJ which provides the capability to register a language server just with settings https://github.com/redhat-developer/lsp4ij/blob/main/docs%2FUserDefinedLanguageServer.md

[joshuataylor]

We should 100% add it to this, or make this plugin ab optional(?) requirement. Depends how much can be done with the LSP, honestly.

[joshuataylor]

I suggest that you try LSP4IJ which provides the capability to register a language server just with settings https://github.com/redhat-developer/lsp4ij/blob/main/docs%2FUserDefinedLanguageServer.md

Didn't see this reply - this looks really, really cool. I'll see how far I get with it, but if we could deprecate this plugin in favour of that, even if we need to use that + another "helper" plugin to fill in the missing bits, that would be fantastic, honestly. LSP has been the future for years.

And of course - https://blog.jetbrains.com/platform/2025/09/the-lsp-api-is-now-available-to-all-intellij-idea-users-and-plugin-developers/

elixir-lang/expert#112

[angelozerr]

I suggest that you try LSP4IJ which provides the capability to register a language server just with settings https://github.com/redhat-developer/lsp4ij/blob/main/docs%2FUserDefinedLanguageServer.md

Didn't see this reply - this looks really, really cool.

Glad you liike the idea.

I'll see how far I get with it, but if we could deprecate this plugin in favour of that, even if we need to use that + another "helper" plugin to fill in the missing bits, that would be fantastic, honestly. LSP has been the future for years.

I let you to test it.

When it will work and if you like it we can discuss how to integrate the language server : in an IJ plugin? In an lsp4ij template?

And it seems it exists an elixir dap debugger. Lsp4ij provides also dap support, see https://github.com/redhat-developer/lsp4ij/blob/main/docs%2Fdap%2FUserGuide.md

And of course - https://blog.jetbrains.com/platform/2025/09/the-lsp-api-is-now-available-to-all-intellij-idea-users-and-plugin-developers/

Indeed, but the sources are not available which can be annoying if you need to debug it.

And lsp4ij provides more lsp support for the moment like codelens than lsp from jetbrains. See https://github.com/redhat-developer/lsp4ij/blob/main/docs/LSPSupport.md

elixir-lang/expert#112