ThinkRail from JetBrains

JetBrains has released ThinkRail, an open-source agentic IDE that pairs AI agents with developers through an integrated workspace system. The tool uses isolated git worktrees to allow multiple agents to work in parallel without affecting the main codebase, and employs spec files as the source of truth for project intent that the agent can read and maintain. ThinkRail is available for macOS, Windows, and Linux, featuring a Monaco-based editor interface with integrated terminals and diffs.