I was using Vimwiki for this stuff for long, but this idea seems promising for a daily journal.

I mostly divide my tasks by day so I don't want timestamp to be added everytime I add an entry. Here's my aliases if it helps:

  alias ndid="nvim +'normal Go' +'r!date' +'normal o' +':exe \"normal i=============================\<Esc>\"' ~/Dropbox/did.txt"
  alias did="nvim +'normal G' +startinsert ~/Dropbox/did.txt"

So use `n(ew)did` at the start of the day and for every subsequent entries, use `did`. Also using Dropbox as storage for portability.