- GNU/Linux + i3wm; complete control over my programming environment.

- bash + GNU coreutils; seriously, take the time to be able to write helpful bash scripts which can run basically anywhere.

- git; use it even when you're not pushing to a remote. Add helpful aliases for everyday commands. Build a good mental model of commits and branches to help you through tough merges. ( my ~/.gitconfig: https://gist.github.com/jeaye/950300ff8120950814879a46b796b3... )

- Regex; combined with bash and your GNU tools, a lot can be done.

- Vim; modal editing and vi-like navigation can blow open your mind. Explore the existing plugins to accomplish everything you want to be able to do. It's all there. ( my ~/.vimrc: https://github.com/jeaye/vimrc )

- Functional programming; if you're new to this, start with Clojure, not one of the less-practical languages. This has made such a huge impact on the way I think about code, write code, and design code that it's possibly the biggest one here for me.

> Vim; modal editing and vi-like navigation can blow open your mind. Explore the existing plugins to accomplish everything you want to be able to do. It's all there.

The reason I end up ditching Vim after a few weeks every time I try it (4 serious attempts now) and go back to IntelliJ (which I’ve used for two decades) is that I never found a solution to the following trivial issue:

Imagine you have a large Java codebase and you want to refactor all occurrences of a method called “doFoo()” to give it a better name - how do you do this in Vim?

This is a single keypress in IntelliJ and I use this function very frequently but I never found a way to do it in Vim.

Note: I only want to change THIS doFoo() method, not the hundred other doFoo() methods in the codebase.

Also note: yea, this includes all implementations of the interface, all abstract classes, all classes that extend a a class that implements the interface and all other funky polymorphic things, and NO unrelated code. And do it all in one keypress, don’t have me manually go through line by line.

Any ideas if this is possible now?

https://github.com/eclipse/eclipse.jdt.ls

https://github.com/georgewfraser/java-language-server

Are both good examples. You'll need a corresponding client like this one

https://github.com/prabirshrestha/vim-lsp

There are others, but this one is pretty good. Next release of Neovim will have one built into the editor. Frankly, it's a bit of a hassle but once you get an LSP provider set up you can get one for just about any language you're using