How we broke Cowork out of the sandbox.

My Claude sandbox could write deploys but couldn’t ship them. Two months of paste blocks. Twenty minutes with Tailscale to break out.

In The Shawshank Redemption, Andy Dufresne crawls through five hundred yards of sewage pipe and steps out into a thunderstorm. He pulls off his shirt and puts his arms in the air.

That moment is the whole film. Not the rock hammer, not the years of digging. That one frame, where the wall is gone.

The Claude desktop app runs an isolated sandbox that cannot reach my Mac mini two metres away. For weeks every deploy ended the same way: Claude wrote a shell script, I ran it on my Mac, I read the output back. The scripts were usually right. When they were wrong I did the recovery, because Claude could not see the machine the script ran on. This morning I asked Claude to ship Famflix live. Claude returned another clean paste block. I wrote back two words. Liar. Solve the sandbox.

The fix took twenty minutes.

Tailscale runs a mesh VPN. The mini already had it installed for an unrelated reason from weeks back. I generated a reusable auth key. I installed Tailscale on my Mac from the App Store. The mini and my Mac were now on a private network with their own DNS zone, tailf7afc5.ts.net.

One command from my Mac:

ssh anthony@cowork-mini.tailf7afc5.ts.net 'hostname && uptime'

The mini answered. Same machine, new address.

Next session, Claude installs the Tailscale daemon inside the sandbox in userspace mode, joins the same network, reaches the mini at the same address. No paste blocks. Claude writes, runs, reads its own output, fixes its own mistakes.