Run six live coding sessions in one native Mac workspace. Choose Claude or Codex—including Sol when your account offers it—and switch without losing the working thread.
Start in Claude. Move the same task to Codex when you want a different model, a fresh limit pool, or Sol. Atelier carries a bounded checkpoint of the visible work and keeps both native sessions ready when you switch back.
Drafts and history stay with the task. Hidden reasoning, provider credentials, OAuth sessions and private caches stay with the provider.
Shared tabs, drafts, attachments and history across providers—plus the deep agents, loops, harnesses, hooks, skills and plugin controls built around Claude Code.
Run six side by side; choose Claude or Codex per task and see the active provider at a glance.
Build and route to custom agents - isolated context, per-agent model and tools.
Set a goal, a verifier and a turn budget; watch it run to a finish line.
Wrap long tasks in a disciplined cycle with a progress file and checkpoints.
Deterministic control at every event - toggle PreToolUse, Stop and more, no JSON.
Install, pin per project, or fork a skill into its own context.
See each provider's servers and import compatible project config without copying credentials or OAuth.
Browse marketplaces; bundle your setup to share with the team.
Claude sessions and Codex threads in one rail—find or resume the work without spending a turn.
Rewind a session to any point; set model, dir and permissions per task.
Give Claude a goal it can check, a verifier to grade the work, and a turn budget so it can't run away. Atelier builds the loop, watches every turn, and stops at the finish line.
For longer work, wrap it in a harness - a plan → work → review cycle with a progress file and checkpoints, so a fresh context picks up exactly where the last left off.
Build custom agents - a reviewer, an explorer, a test runner - each with its own prompt, model and tool access. Atelier gives /agents a real editor.
Each runs in its own context and reports back a summary - the exploration noise never lands in your main session. Delegate the heavy work, keep your window clean.
Atelier talks directly to the installed claude binary and the local Codex app-server. Claude uses your Claude login. Codex uses the ChatGPT/Codex subscription already signed in on your Mac.
There is no Atelier cloud in the middle and no provider key to paste into Atelier. Files stay local; each provider keeps its own credentials, config, MCP OAuth and native history.
Atelier is free for macOS. Your Claude and ChatGPT/Codex plans stay exactly where they are—under your control.
Download for Mac · .dmg