Incredibly valuable for me. When exploring something new, I journal as I go. If a side task has to be parked, I can pick up again months later because I use it as a knowledgebase. Also, a quick scan for #gotcha in my notes reminds me of subtle bugs and workarounds in tools and processes that are easily forgotten. I also create quick reference charts for tools I want to become familiar. I hashtag every new note as if I'm making a Twitter post, so things are linked in a useful way. I usually have Obsidian open near the IDE.

Does the software itself have value? Isn’t it what people do with the software that really has value? The software sat on a floppy disk has pretty low value.

I’d then argue that software has as much value as notes do. It’s about what you do with it/them, what it/they enable - that counts.

But both software and notes are therefore extremely valuable to the activity of doing.

My notes are my software, heck I even call my note system “LifeOS”, which makes that even more apparent.