Been working with multiple document API's recently for my start-up. It's been a real challenge to understand how different document stores compare -- Confluence

Been working with multiple document API's recently for my start-up. It's been a real challenge to understand how different document stores compare -- Confluence uses undocumented XML markup that "mostly" mirrors HTML, Google Docs gives you sometimes semantically-incorrect HTML with lots of inline styles, Slack has its own funny Markdown, etc. Then there's Notion blocks. I had to write my own HTML-to-Notion block parser, but I think I prefer working with it over everything else because structured data is just easier. One interesting gotcha: if you want to completely overwrite a page you currently have to remove every content block one at a time, and then add each new line one at a time. This is using their undocumented API, but the new API doesn't even offer deleting content yet. I'm eager to switch over but it may be a while...