Ledge

Ledge is a notebook app for developers and DevOps engineers who keep commands in their notes. Write a note, press ⌘↩ on any code block, and its output streams right beneath it. It runs in your shell, in your project, on your machine or on a remote server.

Each note has its own persistent shell, with environment variables and working directory carrying across runs. It supports Python, Node, Ruby, PHP, SQL, TypeScript, and Redis out of the box, and you can add any interpreter with one line. You can also run blocks on remote machines over SSH, and self-host the server for free.

Fully open source under Apache 2.0, available on macOS, Windows, Linux, iPhone, and iPad. Ships an MCP server for connecting AI agents like Claude Code, and keeps your notes as plain Markdown files you can sync via iCloud, Git, or anything else.