[bencelaszlo]

Joplin, an open source, extendable, Markdown-based hierarchical note-taking app: https://joplinapp.org/

It lets you choose a synchronization backend, offers applications for every major desktop and mobile OS (also has a terminal version). You can create notebooks and subnotebooks to organize your notes. You can also add tags for better search experience. I created notebooks for specific domains (work-related, home improvement, etc.) and also keep a "temp" for quick notes and W.I.P. snippets.

Its only con that it uses Electron on desktop which causes relatively slow start of the application.