cemd

cemd is an editor I built for writing Markdown files without leaving the terminal. It is written in Go and distributed as a single executable. It lets me see the text I write and its formatted preview side by side on the same screen.

Purpose

I write most of my documents, notes and project descriptions in Markdown. When working in the terminal, switching to another tool just to see how the result would look broke my flow. I made cemd to bring writing and previewing together in a single terminal window.

How it works

When the program opens, the screen is split in two. The Markdown source is on one side and the formatted preview on the other. The preview updates live as I type. The two sides scroll together with line mapping, so whichever section I am in on the source side, the same section is visible in the preview.

There are three view modes: editor only, preview only, and a split screen with both side by side. The theme is chosen automatically based on whether the terminal has a light or dark background.

Key features

• The preview updates live while typing.
• The source and the preview scroll together with line mapping.
• There are three view modes: editor, preview and split screen.
• Undo and redo are supported.
• Text can be searched.
• Mouse navigation and scrolling are supported.
• A light or dark theme is chosen automatically to match the terminal.

Technical stack

cemd is written in Go. I use Bubble Tea for the terminal interface, Glamour to render Markdown in the terminal, Lipgloss for layout and colours, and Chroma for syntax highlighting in code blocks. Bubble Tea is a framework for building terminal applications around state and messages.

The program compiles to a single binary and runs on Windows, macOS, Linux and Android. AppImage and .deb packages are prepared for Linux. The project is released under the MIT licence.

Use cases

• Editing README or documentation files on a server over SSH while seeing the result immediately.
• Keeping Markdown notes in environments without a graphical interface.
• Writing Markdown in terminal environments on Android.
• A practical tool for anyone who prefers the terminal and wants a preview without leaving the editor.