Cydonia vs Nimbalyst
Both are MIT-licensed, local-first desktop apps that keep agents' work as documents and boards. Nimbalyst runs Claude Code and Codex; Cydonia runs any ACP agent.
Checked against each product's own site on
Nimbalyst, formerly Crystal, is the closest tool to Cydonia: both are open source, both keep files on your disk, and both give agents something more lasting than a chat. They differ in which agents they run and in what they let you write.
| Cydonia | Nimbalyst | |
|---|---|---|
| License | MIT | MIT |
| Platforms | macOS, Linux, Windows | macOS, Linux, Windows; an iOS companion |
| Agents | Any agent in the ACP registry, or a command of your own | Claude Code, Codex; OpenCode and Copilot in alpha |
| ACP | Yes | No |
| Documents | Markdown articles with covers, highlighted code and links to sessions and cards | WYSIWYG Markdown, spreadsheets, Excalidraw |
| Boards | Boards of cards, sent to sessions | A session kanban and a task tracker |
| Price | Free | Free for individuals; paid team wiki |
When to pick Nimbalyst
- You want to follow sessions from an iPhone.
- You want spreadsheets and Excalidraw drawings next to your documents.
When to pick Cydonia
- You run agents beyond Claude Code and Codex: Cursor, OpenCode, pi, Gemini, or anything else that speaks ACP.
- You want agents to read and write your articles and boards themselves, through Cydonia's MCP tools.
- You want every article, board and session to carry a stable number, such as
#12, that agents and links can name.