I use it with RubyMine and it works very well for me. I get autocomplete, jump to definition, debugger, test runner, etc.
Not sure which JetBrains IDE in particular you are using, but the single language (‘small’) IDE’s don’t have a global SDK setting like IntelliJ itself does, but once set for a project, it should remember it. You just have to remember to do it when you open an existing directory as a ‘new project’ in the IDE the first time or you’ll get a message that the Elixir Facet SDK is not defined.
Depending upon the OS and how you installed Elixir/Erlang, you may just not be pointed at the correct directory. Open the options under Elixir in the Languages & Frameworks under settings and make sure that both the Elixir and Erlang directories are pointed at legit locations for your installations. I have had situations where setting it from the top level didn’t set both correctly underneath so I always set both underneath by expanding the setting menu. I’m on OSX and have used it with both HomeBrew, and now ASDF installations of Elixir and Erlang with no problems.
If you still have problems, open an issue on GitHub or message @KronicDeth. He’s usually quite responsive and helpful.
EDIT - so I just tried it with a NEW project and you are correct that you can’t get the SDK to set for some reason. My older projects work fine. I see a few others posting the same…I just haven’t created one from scratch yet. Hopefully, he’ll have an update out soon.
EDIT #2 - OK for RM I have a work around that may be similar to what you’re doing. It seems there is a bug in the latest JetBrains IDE where it won’t let you set the main Ruby SDK if you open an existing directory as a project. In the small IDE’s the primary language SDK has to be set in order to set the Elixir SDK. Since RM is not setting the Ruby SDK, the plugin cannot set the Elixir one as an addon module. What worked for me was to create an empty Ruby project and specify a Ruby SDK. This creates literally an empty directory…then do mix new with that same directory name and let it write into that directory. The Ruby version sticks, allowing setting of the Elixir one. I think this is more a JetBrains issue than an issue with the Elixir plugin.