Neovim

I have been preparing for this question.

https://nvim-orgmode.github.io/ is very good and very customisable while keeping consistent and open file file format that allows your notes to be easily stored and read by other apps.

For longer form notes https://github.com/chipsenkbeil/org-roam.nvim/blob/main/DOCS.org can also help while maintaining all the benefits mentioned above.

There is also https://github.com/nvim-neorg/neorg that is trying to create new file format and ecosystem around it. Seems cool, but a bit new imo.

If you're used to markdown in Obsidian, you could look at vimwiki to use a similar syntax in vim. I find it works fairly nicely for standard notetaking, and is a lot faster to start than Obsidian.

Wiki.vim https://github.com/lervag/wiki.vim

It let's you create a wiki with links between pages.

Unlike obsidian, it doesn't put your personal data in the cloud.

Unlike the similarly named vimwiki it doesn't use a custom file format. It uses markdown. Although I think you can configure vimwiki to use markdown as well, but with reduced functionality of the plugin.

I use obsidian.nvim. It's a Neovim interface to my Obsidian vaults, so I can work on my knowledge base in whichever app works best in the moment.

I like zk-nvim

I edit files with vimwiki. I view them in obsidian.

Or at least I used to, I wrote a few little functions to do zettels now, but the linking and traversal features of vimwiki are still really useful.