DoCatz is the container cat of the Catzoid family — if it fits, it ships. It is a fast, light Docker engine and
a container manager in one app: a small Linux VM (on Windows, a WSL 2 distro) runs Docker, and the window shows your
containers grouped by compose project, with their logs, a terminal, their files and their stats. Every container gets
a name of its own, like https://web.shop.docatz.localhost.
It is free and open source (GPL-3.0). There is no account to make and no paid tier. The DoCatz page has the short tour; this page and the ones after it are the full guide.
What you need
- macOS 13 or later, on Apple silicon or Intel. DoCatz runs its VM on Apple’s Virtualization framework, which is why older systems are refused with DoCatz needs macOS 13 or newer (Apple’s Virtualization framework).
- Windows 10 or 11 (x64), with WSL 2 and virtualisation turned on in the PC’s BIOS / UEFI (SVM Mode on AMD, Intel VT-x on Intel). DoCatz checks both and can install WSL for you — see Install WSL. In a virtual machine, its host has to allow nested virtualisation.
- About 1 GB of downloads on the first start, and room on the disk for your images and volumes.
On Apple silicon, Rosetta runs linux/amd64 images next to the native ARM ones. It is on by default.
Windows on ARM: there is no ARM build of DoCatz for Windows. The x64 build runs under Windows’ own emulation, and DoCatz sets up its WSL distro for the PC’s real ARM processor. That combination has not had much testing yet; if you try it, a bug report helps.
Install DoCatz
Download the DMG from catzoid.com/docatz/download. The page picks the right build for your Mac (Apple silicon or Intel). Open the DMG and drag DoCatz onto Applications. The app is signed and notarized by Apple, so it opens without warnings, and it updates itself.
Homebrew works too. The first time, Homebrew asks you to trust the Catzoid tap, because it is not one of its own:
brew tap catzoidhub/catz && brew trust catzoidhub/catz
brew install --cask docatzDownload DoCatz-Setup-<version>.exe from catzoid.com/docatz/download. It installs for your
account only, with no administrator rights. Its pages: Welcome, Only me or Anyone, the install folder,
then Shortcuts — DoCatz is always added to the Start menu, and Create a desktop shortcut is a checkbox. The
last page, DoCatz is ready, has Open DoCatz now.
The Windows installer is not code-signed yet (why): the first time, Windows SmartScreen may say Windows protected your PC. Choose More info → Run anyway. After that DoCatz updates itself.
If Windows does not have WSL 2 yet, DoCatz offers to install it after the first start.
The first start
The first time you open DoCatz, the Welcome to DoCatz dialog says three things to know first:
- First · What Windows needs — the WSL 2 and virtualisation checks. When something is missing, the main button reads Install WSL (or Restart now once WSL is installed and Windows needs a restart). Closing the dialog at that point hides it only for now: it comes back after the restart. When everything is on, the card reads Windows is ready.
- Set up the engine — a small Linux VMdistro in WSL 2. The first start downloads about 1 GB and takes a few minutes; after that it starts in seconds. Set up now opens the Engine page and starts it.
- Your docker keeps working — DoCatz brings its own
docker,composeandbuildxand adds adocatzcontext. Nothing switches until you choose Use DoCatz as the default on the Engine page (below). - A domain for every container —
https://web.shop.docatz.localhost, shared with DevCatz. A DevCatz found badge shows when DevCatz is on this computer.
Everything DoCatz downloads goes into one folder, ~/.docatz, and is checked against a known checksum first. The
footer reminds you that AI is off until you turn it on in Settings → AI; What DoCatz sends opens
What the apps send.
Get started opens the Engine page and starts the engine; Maybe later just closes the dialog. While the engine sets up, the Engine page lists each step. On a Mac: Download the VM manager (Lima), Create the Linux VM, Start the VM and Docker, Connect to Docker — the first start downloads Ubuntu and installs Docker inside.On Windows: Download the Linux image, Create the WSL distro, Start Docker, Connect to Docker. The details are in The engine.
The DoCatz window
The rail
The column on the left switches between the sections. Each one has a shortcut:
| Rail item | Shortcut | What it holds | Guide |
|---|---|---|---|
| Containers | mod+1 | Your compose projects and containers, each with its own page | Containers and compose projects |
| Images | mod+2 | Images, their size and who uses them; pull and remove | Images, volumes, networks and builds |
| Volumes | mod+3 | Named volumes, their project and size | Volumes |
| Networks | mod+4 | Docker networks and who is on them | Networks |
| Builds | mod+5 | Every docker build and compose build, with its log |
Builds |
| Engine | mod+6 | The VM or WSL distro, resources, your docker command line, disk use | The engine |
| Monitoring | mod+7 | CPU and memory of everything running, per project | Monitoring |
| Commands | mod+8 | Ready-made docker commands to copy or run | Commands |
| Settings (bottom) | mod+, | General, Domains, AI, Updates and About | Settings and shortcuts |
A number on Containers counts what runs, and a dot on Engine shows its state. A dot on Settings means an update is waiting.
Back and forward
‹ and › at the top of each page move back and forward through the screens you visited, like a browser; right-click one to jump to a recent screen. mod+[ and mod+] do the same, and so do the back and forward buttons on a mouse.
DoCatz keeps running in the menu barsystem tray when you close the window — see The menu bar and tray.
Your docker keeps working
DoCatz does not take over the docker command you already have. After the first start, it has:
- its own
docker,docker composeanddocker buildxin~/.docatz/bin, - a Docker context called
docatzthat points at its engine.
Until you change something, your terminal talks to whatever engine it talked to before, and you reach DoCatz with
docker --context docatz …. Docker Desktop or OrbStack can stay side by side. When you want plain docker to use
DoCatz, turn on Use DoCatz as the default in Engine → Docker command line. That makes docatz the current
context; turn it off to switch back. The same card can put DoCatz’s docker on your PATH and copy a DOCKER_HOST
line — see Docker command line.
Coming from another engine? Move from another Docker on the Engine page copies your images and named volumes from Docker Desktop, OrbStack, Colima or Rancher Desktop onto DoCatz’s engine, and leaves the originals where they are — see Move from another Docker.
With the other cats
DoCatz works on its own and gets more useful next to its siblings:
- DevCatz runs a site’s
docker-compose.ymlon DoCatz from its Docker tab, and Open in DoCatz shows those containers here. Both apps share one default domain, one local HTTPS certificate and one set of names without a port. - The theme, the AI connection and the site address are shared with Catzoid apps. DoCatz also lists
its containers in a small
bridge.jsonthe other cats can read. - Open in DialCatz on an API’s container hands its project to DialCatz: an environment with the services’ addresses and the routes as a collection. It shows only where there are routes to import.
- Open in DBCatz on a database container opens it in DBCatz at
127.0.0.1:<port>, signed in as the container was started, and goes straight to that service; running database services show up in DBCatz by themselves under DoCatz services, and DBCatz’s Open in DoCatz comes back to the container’s page. - When a sibling is not installed, Download & Install fetches its build for this computer from catzoid.com (more).
All of it is in With DevCatz, DBCatz and DialCatz.
Mac and Windows
DoCatz is the same app on both — every section, the compose tools, domains, HTTPS and AI. What sits underneath differs:
| macOS | Windows | |
|---|---|---|
| The engine | A Lima VM (Ubuntu) on Apple’s Virtualization framework | A WSL 2 distro of its own, docatz (Alpine) |
| Before the first start | Nothing | WSL 2 and virtualisation in the BIOS / UEFI; Install WSL sets WSL up |
| CPUs, memory, disk | Sliders on the Engine page | Set for every WSL distro at once in %USERPROFILE%\.wslconfig |
| Intel images on ARM | Rosetta, on Apple silicon | — |
| When you quit DoCatz | The VM keeps running | The engine stops with DoCatz |
DOCKER_HOST |
unix://~/.docatz/run/docker.sock |
npipe:////./pipe/docatz_engine |
| Menus | The menu bar | No menu bar: the ☰ button at the top left opens the same menus, and every shortcut works with Ctrl |
| Quit | Quit DoCatz | Exit DoCatz |
| Commands → Run | Opens Terminal | Opens PowerShell |
| Live reload in a container | Works as usual | A project on a Windows drive needs polling — see Live reload on Windows |
| DevCatz Services | — | DevCatz’s message gateways, and Typesense, Sonic and Sockudo, show in their own group (more) |
| Install | Signed DMG or Homebrew | Per-user installer, not code-signed yet |
| Uninstall | The app goes to the Trash | DoCatz’s own uninstaller; data goes to the Recycle Bin |
Menu paths on these pages — File → Open Compose File…, Help → Report a Bug… — are the Mac menu bar. On Windows the same menus open from the ☰ button.
Where to go next
- The engine — the VM or WSL distro, its statuses, resources, your docker command line, the bundled versions, disk use, moving from another Docker, reset, and installing WSL on Windows.
- Containers and compose projects — the list, favorites and groups, a container’s logs, terminal, files and stats, a project’s page, the compose editor, Monitoring and Commands.
- Images, volumes, networks and builds — what takes the space, who uses it, and clean-up that lists what goes first.
- Domains and environments — a name for every container, HTTPS, names without a port, DNS, and
a project’s own
.envin DoCatz. - AI in DoCatz — Ask DoCatz, Explain with AI, writing and fixing compose files, and exactly what is sent.
- Settings and shortcuts — every setting and shortcut, the tray, updates, where data lives, the other cats, uninstalling and troubleshooting.
Last updated 2026-11-03