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Claude Code and Codex, with a real terminal around them.

Chat is for conversation. A sandbox gives an engineer a full terminal — git, build tools, the filesystem — with an interactive coding agent running inside it, on infrastructure you control.

zero local setupa real machinebrowser or your terminalsyncs with your editorexpose a port
sandboxes.agyn.dev/calm-otter-27aad18c
agyn sandboxesSandboxescalm-otter-27aad18c
RunningEnvironment claudeIdle timeout 30mExpires in 2d 19hPortsNone
Claude Code
root@workload-ef3095cb /workspace # claude
Claude Code v2.1.225
Welcome back!
Opus 5 (1M context) · API Usage Billing
/workspace
Tips for getting started
Ask Claude to create a new app or clone a repository
What's new
Check the Claude Code changelog for updates
▸▸ bypass permissions on (shift+tab to cycle) · ← for agents
$ agyn sandbox start

Claude Code in a browser tab, ready to work

Start a sandbox and the coding agent is already there — in the image your platform team chose, with the tools installed and the credentials it needs. Nothing to set up locally, and no API key on anyone's laptop.

It runs under the same environment and egress rules as your unattended agents, so an engineer experimenting is inside the rules — not around them.

Environments · 1 feature
$ agyn sandbox start --env claude
  workspace  devcontainer-go:1.2.0
  secrets    3 · never on your laptop
  egress     4 rules · inherited
$ claude
  Claude Code v2.1.225 · /workspace
$ claude

A real machine around the agent

The agent sits in a terminal on a real machine — filesystem, git, build tools. Run the tests it just wrote. Start the dev server it just fixed. Check out a branch and let it continue there.

Everything a coding agent can do, you can watch, interrupt, and steer.

Sandboxes · 4 features
$ git switch -c fix/order-totals
$ claude "fix the rounding in order totals"
editing services/orders/totals.py
$ pnpm test orders
  ✓ 214 passed
$ agyn sandbox connect

Work from the browser, or from your terminal

The browser tab is the quick way in, not the only one — the CLI attaches the very same session from the terminal you already live in.

Either way, the session runs on the platform: close the laptop at six, reattach in the morning, and the refactor finished without you. Stopping keeps the workspace.

Sandboxes · 4 features
# from your own terminal, next morning
$ agyn sandbox connect calm-tiger
  reattached · claude finished the refactor
  41 files changed · tests passing
$ agyn sandbox stop calm-tiger
  workload stopped · workspace kept
$ agyn sandbox sync

Your editor, their filesystem

Two-way sync keeps a local directory and the sandbox reconciled — you edit in the editor you already have, while the code runs where the credentials are.

Sandboxes · 4 features
$ agyn sandbox sync start ./api
  ./api ⇄ /workspace/api   watching
  ↑ 2 files · just now

Expose a port, open it in your browser

A dev server inside the sandbox is one click from your browser — expose the port and the app hands you the URL.

It lives on your platform's private network: any enrolled device can open it — handy for showing a teammate — and the public internet cannot.

Private networking · 3 features
Ports:3000
calm-tiger-533306e4.acme.agyn
:3000http://…acme.agyn:3000
Expose a port
Open from a device enrolled on the platform network. Anyone else on it can reach these too.

See it on your own cluster.

Thirty minutes, your infrastructure, your stack. Or skip the call — it is one Helm release onto a cluster you already run.