Anything that would be considered plaintext (markdown, org, etc…) or something easily portable like html export.

I always think about these things in the sense of how would i pass this journal on to less technically capable family members if it became necessary.

Nice looking project. Will there be amy export/backup functionality? I wouldnt want to keep a journal in a young project that doesnt have some sort of migration option.

Im pretty appimage is stable to use on your system. It contains all of the dependencies inside of it. Just one file for all of its needs. Only issue that ive had is that you need to manually update them (ie download the newest version).