Security

The bridge runs on your computer

You pair a computer from the workspace. The bridge stays on that computer. It starts the project there, and the edit happens there.

It keeps an outbound connection to Butterneck, which relays the share link and the chat. It updates itself from Butterneck's server.

It edits the project you connected

You pick the folder. The assistant is limited to that folder, or to the folders you attach as one project. It is told not to write anywhere else.

Secret settings are on an ignore list

Files named .env are on the ignore list, including .env.local and the same names in subfolders. You can add more paths. The assistant is told to refuse a request that needs one of them.

That assistant is the coding tool already signed in on the computer. Nobody is at its terminal to click allow, so Butterneck starts it with its own permission prompts turned off: Claude Code and Antigravity with --dangerously-skip-permissions, Cursor with --trust and --force. So the folder limit and the ignore list are instructions to the assistant, not a hard block. Butterneck does not put a separate locked-down operating system around it. Connect a development computer that has no production secrets.

You publish

Butterneck does not merge and does not deploy. When the preview looks right, your team publishes the way you already do. Until then the change isn't published.

Who can send a request

Each connected computer starts with a chosen list of people who can send requests. The person assigned to that computer is always on it. "Anyone with the link" is a setting you turn on.

The share link is unlisted, not private. Anyone who has it can open the preview. Every request runs the coding assistant on your computer, so keep the list unless that computer holds nothing you would mind.

The coding assistant sees the project

The edit is made by Cursor, Claude Code, or Antigravity, whichever is signed in on that computer. That provider receives what the assistant reads in order to make the change.

Butterneck does not copy the repository to its servers to edit it. The preview is the app running on your computer. The share link relays that page so someone else can open it. Chat messages and attachments are stored in the workspace.