[ Backed by Y-Combinator Combinator ]

Open-source agentic development environment

Run agents in parallel, schedule repeat work, preview apps in the built-in browser, and manage prompts, skills, and MCP tools from one place.

Use any coding agent — no lock-in. On macOS, Windows, and Linux.

[Over 1M downloads]
showcase
[ Core Workflow ]
Advanced optionsWindows installer missingPlease fulfill various indicators according to the task objectives and connectwith relevant personnel.bug
Integrate Agent Client Protocol (ACP)Please fulfill various indicators according to the task objectives and connectwith relevant personnel.featAllow choosing terminal backendPlease fulfill various indicators according to the task objectives and connectwith relevant personnel.feat
filterLinearJiraGitHubGitLab

Pass issues directly to agents.

Pull from Linear, Jira, GitHub, Notion, Asana, and more. The agent gets full context.

[ Issues ]
mainHEAD 3f9a2c
wt/rewrite-auth
>rewrite auth token flow
>Readsession.ts
>Editsession.ts
>Editlib/keys.ts
>Bashpnpm test
●14 passed
running · 4m
wt/fix-ci
>fix failing CI
>Readci.yml
>Editretry.ts
>Bashpnpm lint
>Bashpnpm test
●lint + types ok
running · 1m
wt/review-pr
>review PR #1284
>Read12 files
>Grepconsole.log
>Editreview.md
>Bashpnpm build
●checks passed
done · 8m ago

Run agents in isolated workspaces.

Parallel tasks across separate Git worktrees — each keeps its branch, terminal, conversation, and review state together.

[ Parallel Agents ]
TASKS
fix-login
rewrite-auth
fix-ci
Emdash — Open-Sour…
Claude Code
http://localhost:3000/

Preview your app inside the task.

Open local apps, remote previews, and browser profiles.

[ In-App Browser ]
src/App.tsxEnter /Commit & Push * 'react'; './App.css'; './components/Hello'; logo = ('./logo.svg'); () { ( <div className="App"> <div className="App-header"> <img src={logo} className="App-logo" alt="logo" /> <h2>Welcome to React</h2> </div> <p className="App-intro"> To get started, edit <code>src/App.tsx</code> and save to reload.importasfromReactimportimportHellofromconstrequirereturnfunctionApp3 7 2 8 1 4 5 6 9 10 11 12 13 14 16 17 18 19Portfoliofrontendserveradd-user...integrat...fix-down...fix-redi...

Review diffs, PRs, and checks.

Inspect changes, commit, push, open pull requests, and monitor CI without switching tools.

[ Review and Ship ]
[ Scale It ]
AUTOMATION DETAILS
weekly bug sweep
Every Mon at 10:00
emdashlandingClaude Codeprompt
runs
●running · 12squeued
●passed · Jun 29 · +214 −38
●passed · Jun 22 · +96 −12

Schedule recurring agent runs.

Automate bug sweeps, release prep, reviews, and checks.

[ Automations ]
Remote Serversrc/App.tsx3 7 2 8 1 4 5 6 9 10 11 12 13 14 16 17 18 19SSH

Run agents on any machine.

Connect over SSH to your dev server, cloud VM, or GPU box. Agents run remotely with full worktree isolation.

[ Remote SSH ]
provision.sh
$
./scripts/provision.sh
→ resolving workspace config from .emdashrc
✓ found image emdash/dev:latest · sha256:8f3e2b1
→ pulling base layer · 142 MB ........... done
→ pulling toolchain · 87 MB ............. done
→ pulling runtime · 24 MB ............... done
→ allocating compute · 4 vCPU · 8 GB RAM
→ mounting /workspace (ext4, encrypted)
→ spawning git worktree for branch dev/jane
→ installing dependencies
+ node@22.11.0 · pnpm@10.0.0 · claude@1.0.4
→ generating ed25519 keypair · ~/.ssh/id_emdash
→ opening tunnel devuser@10.0.1.42:22
→ health check · 4/4 services healthy · 1.2s
→ workspace ready in 11.8s
{
"host": "10.0.1.42",
"port": 22,
"user": "devuser"
}
Connected to 10.0.1.42

Provision workspaces on demand.

Setup and teardown scripts create isolated local, remote, or cloud environments for each task.

[ Bring Your Own Infra ]
[ Coding Agents ]
Use any agent.
Emdash works with 25+ coding agents. Mix and match per task or just use your favorite.
  • Codex
  • Cursor
  • Claude Code
  • Amp
  • Antigravity
Show 29 more
Library for reusable agent resources
Save prompts, install skills, and sync MCP servers to supported agents.
View docs
Detected agentsClaude CodeCodexCursor
Agent setup that understands providers
Detect CLIs, manage install state, wire hooks, and keep provider settings consistent.
View docs
extensioncommandsgrayscale.tsactivate.tsfolders.tsfileColor.tsISSUE TEMPLATEworkflowspr-closed.ymlbuild.ymllabel.ymlclose-... * 'react'; './App.css'; './components/Hello'; logo = ('./logo.svg'); () { ( <div className="App"> <div className="App-header"> <img src={logo} className="App-logo" alt="logo" /> <h2>Welcome to React</h2> </div> <p className="App-intro"> To get started, edit <code>src/App.tsx</code> and save to reload. </p> < name="TypeScript" /> </div> ); } export default App;importasfromReactimportimportHellofromconstrequirereturnfunctionAppHello1 2 3 4 5 6 7 8 9 10 11config.tsApp.tsx
Built-in file editor
Browse, edit, search, and recover files directly inside the task workspace.
View docs
[ Praise ]
What developers are saying.
I've been using Emdash for a few weeks now to develop several projects for macOS and iOS. So far, for me it's the most designer-friendly. Of course, you need knowledge of Git and a few other things to really take advantage of it, but it's simply great.
Carlos
Carlos
@soycanopa
Emdash with Pi is chefs kiss
Matt
Matt
@nzmrldev
This is the first tool I've used besides Claude code that feels like it unleashes coding agents and isn't just bolting them on
James Evans
James Evans
@jamesevans
We need a tool to build the feature. This is it. @emdashsh
Milan
Milan
@wiegard_milan
Once you start using @emdashsh all other IDEs feel like trashsh
Het
Het
@hetdv
I LOVE using emdash. Its 10xed my workflow and could not live without. Thanks for pushing so frequently team!
Sebastian Scott
Sebastian Scott
@sebastian_scott3
Very big fan of Emdash. It's been incredible seeing how fast the team is shipping new features and expanding it. I love how I can run my agents in parallel and also across different models. Finally, I don't have to migrate back and forth between Claude Code and Codex every month.
Dan
Dan
@dan_meier1
This is spot on. I think future of software is async because it gives engineering scale to an individual.
Nitesh
Nitesh
@ArmyOfRobots
I found the winner. The level of polish makes me happy. Support Droid, Hermes, Codex, Pi, and much much more. Clean design, uses terminals as it should.
0xSero
0xSero
@0xSero
Parallel brains, one cockpit. Ship faster 🚀
Libing
Libing
@libing890117
Parallel CLI agents in isolated worktrees is a killer idea! Feels like the foundation for serious agent-native dev environments.
Suhrab
Suhrab
@suhrabautomates
[ FAQ ]
Frequently asked questions.

Emdash (YC W26) is a free, open-source agentic development environment: run coding agents like Claude Code and Codex in parallel, schedule agent work, and review changes in one place. Available for macOS, Windows, and Linux.

Start shipping with

Get product updates

New releases, improvements, and notes from the team.

[ Open Source ]
Proudly open source.
5,200View on GitHub
General Action © 2026
DocsBlogRSSChangelog
About usPrivacy PolicyTerms of Service