> ## Documentation Index
> Fetch the complete documentation index at: https://tesser.sh/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Tesser

> Cloud dev environments that feel like localhost

Tesser gives each git worktree its own Linux machine in the cloud, which we
call a box. The code stays on your laptop. Your coding agent (Claude Code,
Codex, or you at a terminal) runs `tesser` commands that copy the worktree to
the box and run things there, such as the dev server, the test suite, or a
build. The dev server is then available at `http://localhost:3000` on your
laptop, the same address it would have locally, and when several boxes are
running you choose which one that address shows.

```sh theme={"theme":"css-variables"}
tesser exec -- pnpm test     # runs the tests on a box and streams the output back
BOX=$(tesser dev web)        # starts the dev server on a box
open http://localhost:3000   # shows that dev server
```

## What it is for

Tesser is for running several worktrees at the same time without them
competing for your laptop. Each worktree has its own box, so ten dev servers
do not share ports, CPU, or memory, and your browser still uses localhost for
all of them. Boxes keep their installed dependencies and build caches between
runs. When you stop using a box it goes to sleep on its own, and it wakes up
the next time a command needs it.

## What you need

You need a Mac or Linux machine (Windows works through WSL), a git
repository, and a Tesser account. `tesser login` creates the account in the
browser if you do not have one. There is nothing to set up on the box side:
Tesser creates each box with Ubuntu 24.04, Node 22, and rsync installed, and
you install anything else your project needs with `tesser exec`.

Usage is metered per second and shown on the
[dashboard](https://tesser.sh/dashboard). The
[pricing page](https://tesser.sh/pricing) has the rates; nothing is charged
during the private beta.

## Where to go

<CardGroup cols={2}>
  <Card title="Quickstart" href="/docs/quickstart">
    Install the CLI, sign in, and get a dev server running on a box.
  </Card>

  <Card title="Working with an agent" href="/docs/agents">
    Install the tesser skill so Claude Code or Codex can run the boxes for you.
  </Card>

  <Card title="CLI reference" href="/docs/cli-reference">
    Every command and its flags.
  </Card>

  <Card title="How it works" href="/docs/architecture">
    What runs on the laptop, what runs on the box, and what the control plane does.
  </Card>
</CardGroup>