I'm using Deno's built-in formatter, which is very nice and convenient because it mostly does what I want out of the box. I wish it could organize imports better, that's it.
I'm using Codium with the "Atom One Dark" theme, which makes the hideous VSCode editor look a bit more like the beautiful Atom editor that was put to rest last year.
I'm also using the Fira Code font for the nice ligatures. This is a must for me because it makes code so much easier to look at. https://github.com/tonsky/FiraCode