Koi for note taking

Your notes are files ⋅ Organize and search ⋅ File over app

Keep your notes as files. Koi works directly with Markdown, plain text, Org Mode, and other text formats without importing them into a proprietary database.

Your notes stay where you put them and can be opened with any editor, synced with any service, or backed up however you like.

Your notes are files

Point Koi at a directory and use it as your notes folder.

~/Documents/Research
~/Dropbox/Journal
~/Desktop/Notes

You can set that directory as the default file explorer root:

file_explorer_root                  /Users/michael/Desktop/Notes

Koi then opens directly into your notes when it starts.

There is no library to import and no database to maintain. The directory on disk is the structure of your notes.

Organize and search

Use folders and files however you like:

Notes/
├── Work/
├── Personal/
├── Projects/
├── Reading/
└── Journal/

Search works directly across those files using ripgrep, without building a separate database of your notes. Because everything remains on disk, the same directory can be synchronized with iCloud, Dropbox, Syncthing, Git, or whatever else you already use.

Write in any format

Markdown is an obvious choice for notes, journals, project documentation, and personal knowledge bases, but Koi doesn't require it.

Use Markdown, plain text, Org Mode, or another text-based format. A Generic-Default style, inspired by Emacs, is included for plain text and other files where minimal syntax highlighting is preferred.

You could even write your notes in Lua:

meeting = {
    date = "2026-08-04",
    attendees = {
        "Alice",
        "Bob",
    },
    action_items = {
        "Fix benchmark bug",
        "Publish release",
        "Email customers",
    },
}

Should you? Probably not. Koi doesn't particularly care.

File over app

A file-first workflow separates your notes from the application you happen to use to edit them.

You can version them with Git, process them with scripts, search them from the command line, synchronize them with existing tools, or open them in another editor.

Applications change. Text files have been useful for decades.

Koi is built around keeping that distinction simple: the editor is a tool for working with your notes, not the place where your notes have to live.