More recently Obsidian inspired me in terms of showing me what a non-enshittified, open/portable format note-taking experience could be like. And the beauty of simple Markdown notes!
Through the Obsidian community I discovered the concepts of Zettelkasten / Second Brain etc. and was further convinced of the usefulness of regular note taking and storing/synthesising of reference knowledge.
But I found Obsidian slightly mismatched with my requirements. Primarily because there was certain functionality I needed which can only be achieved with plugins, but I didn't consider their plugin security model to be sufficient enough for storing my most confidential data - even with everything being local files. (That and the lack of open source was enough to make me nervous).
My app is written in pure Javascript, heavy use of web components, running in Electron. No Node.js (apart from what Electron is precompiled with) - so no third-party dependencies as part of my code, and Electron is heavily locked down. I have a lightweight build step using Esbuild (a single rust binary).
Being 100% native JS - no frameworks - and quite lightweight, the app is indistinguishable from a native macOS app in terms of responsiveness! Knowing that may not always be the case, I'm also eyeing up Tauri as a potential alternative GUI "wrapper".
As a .NET developer by day I would have liked to have built it in MAUI but found that to be quite lacking for my purposes.
I've started to write a blog article about it with some screenshots - I"ll eventually get around to publishing it!!
How about you? What did you write your backend in and did that escalate into the front-end too?
The CalDav idea is very interesting... you've got me thinking about that.