Switching between projects dragged a bit; I recently switched everything to a monorepo (https://github.com/twitter/commons/tree/master/src/bash/git/...) and now start the IDE from the repo root. Snappy now.

Also exclude node_modules, logs.

I often end up marking node_modules as "excluded", which sucks a bit for autocomplete/intellisense style code insights, but really speeds things up. Switching branches seems to be the primary thing that grinds it to a halt.

If you have the RAM to spare, you can up the [JVM allocations](https://www.jetbrains.com/idea/help/increasing-memory-heap.h...). The setup instructions should be adaptable to other IntelliJ based products.

I remove plugins I don't use - that might help.

Also, as other people have mentioned, "exclude" files from being watched by the editor. I do a lot of NLP and machine learning work and I often have very large text training files in my working repos - important to tell the editor to not to watch these files.