linkding is a simple bookmark service that you can host yourself. It supports managing bookmarks, categorizing them with tags and has a search function. It provides a bookmarklet for quickly adding new bookmarks while browsing the web. It also supports import / export of bookmarks in the Netscape HTML format. Docker optimized but I think it could be run manually.
Needs node.js to compile the JS crap.
Uses SQLite as its back-end. Plus, it's based upon Django so it probably has its own ideas about default databases (and REST APIs).