One of my dearest parts of my system is the knowledge, task, and time management part. There's many things to improve, but I'm really happy to where I got.
TLDR; custom org/markdown/hyperlists-inspired document syntax powered by tree-sitter, go library for accessing the data, command line utility with interactive task manager (built in with a custom React-like component-based TUI framework), Neovim plugins and integrations.
This short video explains more than I can in a short time: https://gist.ro/slang.mp4
Extra - Thank you Org mode: I do my work in a terminal emulator, so (obviously) my editor is Neovim. Two years ago I allocated a few weeks to learn Emacs and to review Org mode, I was hooked on so many concepts, and I loved it. Didn't like Emacs through, it's just too slow for me, and Elisp felt very meh if not yuck. There's quite a few things that I liked so much while testing Org mode, and that I tried to port.