> ## 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. # Boxes > What a box is, the two kinds, and what happens to a box you stop using A box is a Linux machine in the cloud that holds a copy of your worktree at `~/workspace`. Tesser creates boxes, syncs your worktree to them, runs commands on them, and puts them to sleep when they are idle. You do not deal with instance ids, SSH keys, or IP addresses; `tesser status` will show them if you want to see them. Each box is an m7a.large (2 vCPU, 8 GB of memory) with a 40 GB disk, running Ubuntu 24.04 with Node 22, rsync, and Docker (compose included) installed. The `ubuntu` user has passwordless sudo and is in the docker group, so `sudo apt-get install` and `docker compose up` both just work. You can check what else is available with `tesser exec -- which pnpm` and install what your project needs with `tesser exec`. ## Two kinds of box A **workbench** holds your worktree and runs nothing on its own. It is the box `tesser exec` uses when you do not name one, and it is where tests, typechecks, builds, and one-off scripts run. Each worktree gets a workbench the first time it needs one. An **instance box** runs one service's dev server. `tesser dev ` creates one for each combination of worktree and service, so a repository with a frontend and a backend ends up with two instance boxes and one workbench. Keeping these separate means a test run never competes with the dev server for CPU, and an install on the workbench never replaces the dev server's `node_modules` while it is running. ## Creating a box Most of the time you do not create boxes directly, because `exec` creates the workbench and `dev` creates the instance box. `tesser make` exists for when you want a box before running anything on it: `tesser make` creates a workbench and `tesser make ` creates an instance box. Both print the new box id. When a warm box is available in the pool, creating a box takes a second or two. Otherwise a new machine is launched, which takes about 90 seconds. `tesser pool fill` keeps a couple of warm boxes ready if you create boxes often. ## Syncing Every `exec` and `dev` copies your worktree to the box before running. Only changed files are transferred, and `.gitignore` is respected, so `node_modules`, `.env.local`, and build output stay on your laptop. The box gets its own `node_modules` when the `setup` command runs. If a sync would delete most of what is on the box, Tesser stops and reports it, because that usually means the box was created from a different worktree. In that case, create a new box rather than passing `--force`. The copy on the box is a real git repository with a single commit, your current HEAD. `git status` and `git diff` work there, and `git log` shows one entry. Anything you commit on the box is lost at the next sync, so always commit on your laptop. ## Sleep, wake, and removal Idle boxes go to sleep on their own. A sleeping box keeps its disk and its id and costs a few cents a day. Any command that targets a sleeping box wakes it first, which takes about 40 seconds, and if the box had a dev server running it is started again. | | Workbench | Instance box | | ------------- | --------------- | --------------- | | Sleeps after | 10 minutes idle | 2 hours idle | | Removed after | 16 hours asleep | 16 hours asleep | A box counts as idle when no command is running on it and no traffic is reaching it. A test suite that runs for an hour keeps the box awake for that hour, while an SSH session sitting at a prompt does not. You can also act immediately: `tesser sleep ` powers a box down, `tesser stop ` stops the dev server but leaves the box awake, and `tesser rm ` removes the box permanently. None of these ask for confirmation. ## Finding a box `tesser ls` lists every box in the org with its kind, service, power state, and whether it is currently online. `tesser status ` shows the details of one box, including its IP addresses and when it was last active. Both accept `--json`. ## Looking inside a box `tesser ssh ` opens a shell in `~/workspace`, and `tesser ssh -- ` runs a single command there without syncing first. Use these for inspection rather than editing, since an edit made on the box is overwritten by the next sync. To read the dev server's output, use `tesser logs ` for the last 200 lines or `tesser logs -f` to follow it.