Looking for an open source, self-hostable, secure journaling/note taking/"personal Pinterest / Pocket" software. Dated bookmarks with search. Attaching pictures. Writing short notes. Fulltext search, tags. It should work on the go, an app or web interface would work. An extension would also be cool

I have a quite clear idea of the interface and functions. ... But I don't want to reinvent the exact same thing that already exists. Do you use something like that?