Basics

Mitos is a modal editor: the same keys navigate, select, and edit depending on the current mode. This short walkthrough covers enough to edit a file without trying to memorize the entire keymap.

For a guided lesson inside the editor, run ms --tutor or enter :tutor from Mitos.

Open a file

After installing Mitos, open a file or directory from your shell:

ms README.md
ms .

Mitos starts in normal mode. Press Esc whenever you want to return to it.

Image previews

Open an image file the same way as a text file, for example ms screenshot.png. See Image previews for supported formats and terminal rendering.

Move around

Use the arrow keys or the home-row movement keys:

You can prefix many movements with a count. For example, 5j moves down five visual lines.

Insert text

From normal mode, press i to insert before the selection or a to append after it. Type normally, then press Esc to finish the insertion.

Other useful entry points are I and A for the start and end of the line, and o / O for a new line below or above.

Select, then act

Mitos uses a selection → action editing model. A cursor is a one-character selection; movement changes that selection. Press v to enter select mode, where movement extends it, then apply an action:

Press x to select the current line. Syntax-aware textobjects, such as miw for the word around the cursor, are described in Textobjects.

Edit several matches at once

Multiple selections are a normal part of editing, not a separate mode. One simple workflow is:

1. Press x to select a line.
2. Press s, enter a regular expression, and press Enter.
3. Mitos creates one selection for every match in the line.
4. Press Alt-r, type the replacement, and press Enter to replace every selection.

The replacement prompt leaves the document untouched until Enter, then replaces all selections in one undo step. Escape cancels, and submitting empty text deletes the selections. Replacement text is literal, including strings such as $1. The new text stays selected, preserving the primary selection and each selection’s direction. Press . to repeat the committed replacement on the current selections.

Use c to change selections interactively in insert mode. r still replaces each selected grapheme with the next character: selecting hello and typing rx gives xxxxx, while Alt-r, x, Enter gives x.

Use , to keep only the primary selection. The Usage and Registers pages cover more ways to compose edits.

Search, save, and quit

Press / to search forward, then use n and N to move between matches. Press : to enter command mode:

Where to go next

• Read Usage for modes, buffers, selections, and motions.
• Keep the Keymap open as a reference while learning.
• Set up language servers for completion, diagnostics, and code actions.
• Adjust editor behavior in Configuration.