Edmund
July 3, 2026 · View on GitHub
Edmund is a minimal, file-based, native Markdown editor for macOS with inline live preview.
https://github.com/user-attachments/assets/5c9097c7-68d2-4423-b0f5-495979775f6d
Whether as a companion alongside your Markdown knowledge base or as a standalone editor, Edmund blends in with macOS and works seamlessly with your files wherever they are.
Our goal is to be the CotEditor of Markdown editors, i.e. elegant, powerful, configurable, and native inside out.
⚠️ Edmund is currently in beta. See the roadmap for what's coming next :D
Differentiators
- Live preview: Typora/Obsidian-style WYSIWYG.
- File-based: Open
.mdfiles from anywhere. No vaults or dedicated folders required. - Native: 100% Swift. Based on AppKit and TextKit 2. No Electron. Minimal dependencies.
- Fast: Handles ~1-2MB files with ease. No launch lag.
- Extensible: Opt-in math and Obsidian syntax. Extensions system coming soon!
- Private: Offline by default. Optional blocking of external links and HTML sanitization.
See my blog post for more of the motivation and design philosophy.
Screenshots
Installation
Get Edmund.dmg from the latest release, open it, and drag Edmund.app to Applications:
Warning
If macOS reports that the app is 🚧DAMAGED🚧 when you're trying to open it for the first time, fear not.
The app is not damaged. It's just not signed properly because I am not a $99/yr-certified Apple Developer.
Good thing is there's an easy way to bypass the barrier.
To open Edmund (or any other "damaged" app) for the first time, choose one of the following:
- System Settings → Privacy & Security → scroll down → Open Anyway. Or,
- Run the following line in Terminal:
xattr -dr com.apple.quarantine /Applications/Edmund.app- You might also need to prepend the command with
sudo.
- You might also need to prepend the command with
Edmund checks for updates automatically; you can also browse version history here.
Dependencies
Alternatives
If Edmund's not your thing, some of the following might be:
- Closed source
- Obsidian, cyberWriter, Notion
- Typora, Lettera (beta), LitSquare Ink MD
- Open source
The list is by no means exhaustive, and neither was it meant to be. I just wanted to give credit to the makers of these apps, esp. IMO the aesthetic open sourced ones. A comprehensive list may be found here.
Acknowledgements
The following have greatly influenced the architecture and/or helped with design. I owe them many thanks:
- Swift Markdown Engine / Nodes for the parser/token architecture and the TextKit 2 integration
- Typora and Apple Notes for app menu organization
- Tomorrow Light and One Dark for code syntax highlighting
- create-dmg for a Apple-looking
.dmg - MarkEdit for the readme organization
- screenshot-studio for the amazing screenshots editing experience
- shields for the beautiful badges in this readme
- Claude, caveman, and ponytail for the engineering.