How I manage documents if all of them in one flat folder using calibredb.el

You may not know: there is one type of metadata in Calibre, called folder metadata. It is also be used in elink device if you use calibre to transfer files to elink device. A hidden file named .metadata.calibre.

Unlike the original database metadata.db, metadata needs ebooks be resided inside a non-flat folder, while the .metadata.calibre is a json file, and it has all the metadata for all documents/ebooks under one flat folder.

The ultimate Emacs hacking tutorial in Windows 10 WSL 2

Do you think Emacs’s performance in windows is bad? Do you really want to use a native Speed Emacs in Windows? Do you hate the unnatural path transition between windows convention and Linux convention? Do you feel frustrated when you try to install and configure Emacs in WSL? Do you just want to taste the power of Emacs running in WSL 2?