Thinkrail

ThinkRail is an open source agentic IDE that runs on macOS, Windows and Linux. A user opens any local git repository as a project and then creates workspaces, each of which is a separate git worktree with its own branch, files, terminals and chats. This lets several coding agents work in parallel while each one's changes stay on its own branch and the main branch stays clean until the user decides otherwise. The editor surface includes Monaco based tabs, terminals, diffs and concurrent chats. The coding agent is the pi coding agent, which runs in process and handles models, skills, context compaction and cost, while ThinkRail manages the workspace, the editor and the connection between them. A distinctive feature is a spec graph: a connected set of spec files kept beside the code that the agent can read, search and maintain with dedicated tools, so project intent persists between sessions. ThinkRail is aimed at developers who want to run agents in isolated worktrees rather than in their working tree. It is released under the Apache 2.0 license and is listed as a JetBrains InnovationHub project. Installation is by a downloadable app for macOS, Windows and Linux, or by a local launcher that opens a browser interface from the command line. The site publishes no pricing, and the software is free to download and use under its open source license.