Styx vs Emdash
Styx and Emdash are both agentic development environments: several coding agents at once, each on its own branch in its own worktree, with diffs to review before anything merges. Emdash is open source and casts the widest net; Styx is narrower and puts its effort into what agents may touch.
Side by side
| Styx | Emdash | |
|---|---|---|
| Runs on | Mac (Apple silicon); Windows coming | Mac, Windows, Linux |
| Agents | Claude Code, Codex, Gemini CLI, Cursor | 34 CLI agents, incl. Claude Code, Codex, Cursor, Amp, Copilot |
| Price | Free | Free and open source; Cloud and Enterprise prices not published |
| Each agent isolated | Own git worktree and branch | One git worktree per task, with its own branch and terminal |
| Scope of one window | Every project you work on | Not part of its docs |
| Review | Diff with per-hunk accept and reject; checks before landing | Side-by-side diffs, commit, push, pull requests, GitHub Actions checks |
| Your editor | Imports recents, keybindings and theme; opens files back in it | Built-in file browser and editor in each task |
| Secrets | In the macOS Keychain; agents get scoped, expiring access | Not part of its docs |
| Production access | Agents ask; you approve for a set time; Touch ID for live systems | Not part of its docs |
| Audit log | Every request, approval and use, append-only | Not part of its docs |
| Deploy targets | Vercel, AWS, Google Cloud, Supabase, GitHub, SSH | Not part of its docs |
| Cloud workspaces | No: everything runs on your Mac | SSH to your own servers; temporary cloud workspaces |
| Team collaboration | No | Enterprise tier, by contact |
| Issue tracker | No | Linear, Jira, GitHub, Notion, Asana |
“Not part of its docs” means we could not find it in Emdash's own material on 29 September 2026, not that it can never be done with it. Tell us at hello@heystyx.com if something here is wrong and we will fix it.
Where Emdash is ahead
- Open source. Emdash’s code is public. Styx is not open source.
- Every platform. It ships for Windows and Linux as well as the Mac.
- More agents. It supports 34 CLI agents; Styx supports four.
- Issue intake. It pulls tasks with their context from Linear, Jira, GitHub, Notion and Asana.
Where Styx is different
Agents never hold your keys
Useful agents need real things: a deploy, a database, a server. In Styx the credentials stay in your Mac’s Keychain. When an agent wants production, it stops and asks; you approve it for a set time, with Touch ID for anything live, and the access ends on its own. Every request, approval and use goes into a log nobody can edit.
Every project, one window
Styx is built around switching between everything you work on: each project, its agents and the ones waiting on you, one keystroke apart. Nothing is organised around a single repository.
On top of your editor
Styx brings in your editor’s recent projects, keybindings and theme, and opens any file back in it with one key. It is not trying to be the place you write code.
One honest limit: this is a guardrail, not a sandbox. Agents run as you, on your Mac, and an agent that deliberately goes around Styx’s tools is not stopped by them.
Which to choose
Choose Emdash if you want open source, Windows or Linux, the longest list of agents, or tasks straight from your issue tracker. Choose Styx if you are on a Mac, work across several projects, and want agents to ask before they touch anything live.
Download Styx for Mac. It is free. See every comparison.
Questions
Is Styx an Emdash alternative?
Yes. Both run coding agents in parallel, each in its own git worktree. Emdash is open source, cross-platform and supports more agents; Styx adds every project in one window and a gate on production access.
Is Styx open source like Emdash?
No. Styx is free to use but its source is not public.
What is an agentic development environment (ADE)?
An app for managing AI agents that write code, rather than for writing code yourself: several agents in parallel, each isolated on its own branch, with a place to see who needs you and to review what they did. Warp coined the term in June 2025.