ShWiM: peer-to-peer terminal sharing

August 01, 2025

Built on top of Fowl, shwim uses tty-share with localhost-only network addresses over Magic Wormhole (via Fowl) so you get durable, end-to-end-encrypted, on-demand terminal sharing.

Install from PyPI or peruse the source code to get started.

The host types shwim which prints out a magic code, and the guest side types shwim <magic-code>. Now both sides are typing on (and seeing output from) the “host” machine.

Why?

The tty-share project hosts a public service – however, while traffic to the server is encrypted, it can see all content. Also, if you sleep your laptop or disconnect briefly, the connection is gone.

Using the “magic” of a Dilated Magic Wormhole we can easily layer “durability” and “end-to-end encryption” on top of the existing tty-share program (with zero changes to tty-share itself).

Durability

We say a connection is “durabile” when it can survive interruptions and inconsistency while remaining invisible to the application protocol (i.e. tty-share in this case). Magic Wormhole will re-connect on changed IP addresses or other network conditions, correctly resuming the flow of bytes for tty-share right where it left of – it can’t tell if you simply didn’t type or 10 minutes, or re-located to the coffee-shop.

End-to-End Encryption

Only two computers have a shared secret after the Magic Wormhole system produces, and then consumes a “secret code”. This is what happens with shwim. So, no other program (including the Magic Wormhole mailbox server) can decrypt any of the content of any messages.

These secret codes are also one-time use only, meaning there’s a much smaller window when observing / intercepting a code is useful (i.e. before your intended party consumes it). Even if such interception is successful, you will notice: your partner will not be connected.

Why Not X…?

There are many different ways to share terminals and screens. If you have a different system that works for you: great!