JetBrains/thinkrail

ThinkRail is worth a look if you already drive a coding agent from a terminal and want parallel branches, diffs, and PR state in one window. It is a young JetBrains incubator project, and the provided material doesn't establish long-term maintenance.

The problem

You have a repo and want an agent to make a change without leaving your working checkout dirty. The usual loop is: stash or copy the repo, run the agent in a terminal, then manually inspect the diff and shuffle it back into your editor. ThinkRail changes that by making each agent task a git worktree workspace with its own branch, so the agent works beside your checkout instead of on top of it. The result is a parallel branch you review in the same window, with a diff, terminal and file tree scoped to that workspace.

What's different

The mechanism is a thin host that runs the pi coding agent in-process and bridges it to a web UI; pi owns models, skills, compaction, cost and session state, while ThinkRail owns the workspace, editor and protocol project README. In practice that means several concurrent pi sessions per workspace, a Monaco editor with live git marks and terminals, and anchored review comments that can be sent to a chat as structured context. Agents can also be handed failing CI checks or a diverged branch, and the topbar tracks the branch against origin and its pull request. The durable knowledge layer is the notable trade-off: living specs and reusable skills are meant to accumulate project context, but that couples your workflow to ThinkRail's own model of specs rather than to plain files in the repo. Workspaces also settle onto a shelf when their PR merges or closes, or after a quiet week, which is convenient but means state lives partly in the app's own bookkeeping.

Who should try it

Good fit: a solo developer or small team already comfortable with git branches and PRs who wants to run two or three agent tasks in parallel and review them without branch-switching churn. Less good fit: someone who only wants a chat panel bolted onto their existing IDE, or a team that needs an Intel macOS desktop build, which doesn't exist. If you'd rather stay in the shell, the self-contained thinkrail CLI is the documented alternative path and works on macOS Intel by building from source install and platform notes.

Requirements and limitations

Desktop builds have real platform floors: Linux needs glibc 2.38+ plus GTK 3, WebKitGTK 4.1, Ayatana AppIndicator 3 and librsvg 2, essentially Ubuntu 24.04 or newer; macOS desktop is Apple Silicon only; Linux artifacts are unsigned, and the macOS CLI is signed but not notarized. Agent work also requires an authenticated pi provider, so the IDE alone isn't enough. Development needs Bun 1.4.4 and Node.js ≥ 22.19. Analytics are on by default for launches, chats and error reports tied to a random installation ID, though prompts, code and file paths are excluded; --no-analytics or THINKRAIL_NO_ANALYTICS=1 turns off additional sharing for a run project README.

HotRepo's take

The repo was 109 days old on 2026-10-25, when it appeared once on the daily trending board at 1,111 stars and +52 that day; with only a single recorded board date, persistence can't be judged. It is still an incubator project, so treat the extension system and "builds its own capabilities" as a stated direction rather than a shipped guarantee. Before committing, check whether your platform's desktop build and pi provider authentication are both covered in the install notes and project site.