Show HN: Hyperbutler – Docker on Windows 11 Without WSL or Docker Desktop

hyperbutler is an open-source, Docker-compatible engine for Windows. It boots a small Linux VM directly through the Windows Host Compute Service (the API WSL 2 uses), runs dockerd in it, and lets the stock docker CLI and Docker Compose talk to it. No WSL, no Docker Desktop.

v0.1.1. v0.1.0, the first release, passed a 24-hour soak (261,338 docker commands, none failed); v0.1.1 made bind mounts from C:\ about twice as fast. It works end to end on Windows 11 Home. Some release tests have not run yet, among them an install on a clean PC and a real sleep test; status and the release checklist list them. Early software: try it, report what breaks.

No WSL. The VM runs on Hyper-V's Host Compute Service. WSL can stay off, and its updates never touch hyperbutler.

Light. 319 MiB of memory at idle with the broker service, a 120 MB download, 197 MB installed.

Disk space comes back by itself. Delete images and the data disk shrinks. No compaction, no admin step.

Fast bind mounts from C:. Its own file server reads 2000 small files in 0.4 s (Docker Desktop: 3.4 s), and file watchers fire.

Your tools, unchanged. The stock docker CLI, Compose, SDKs and VS Code, through a hyperbutler docker context. Both clients are bundled.

No admin rights for daily use. A small Windows service is the only privileged part, and it only starts and stops your VM (how).

Safe for AI agents. A built-in MCP server lets an AI assistant read and, if you allow it, manage your containers, with limits it cannot lift.

Free for every company size. Apache-2.0, no telemetry.

Measured against Docker Desktop

Same laptop (Windows 11 Home, Core Ultra 7 155H, 32 GB), out-of-the-box settings, the same script, one engine at a time (method and raw data).

Docker Desktop is ahead on breadth: Kubernetes, Windows containers, extensions and a mature GUI. One machine is not a general result.

You need Windows 11 (Home, Pro or Enterprise) on x64 with virtualization enabled in the firmware.

Builds are not code-signed yet: SmartScreen says "Windows protected your PC", so choose More info → Run anyway, after checking the file against SHA256SUMS from the release. Prefer no installer? The zip works too (install guide).

hyperbutler start # boots the VM; the Docker API answers in about 1.5 s docker run --rm hello-world docker compose up -d # in a folder with a compose.yaml hyperbutler status # is it running, and which docker it serves hyperbutler stop

Everything else, from published ports to troubleshooting, is in the docs.

Docker CLI and Compose. The bundled docker CLI and compose plugin are built from pinned source; your own docker CLI works too. Builds, healthchecks, service names, named volumes, bind mounts and published ports are tested end to end (bench/compose). More

Bind mounts and file watching. -v C:\src:/src goes through hyperbutler's own file server; a change on Windows reaches inotify in a few milliseconds, so Vite and webpack rebuild. ADR 0007

Networking. A user-mode network stack: published ports on localhost, host.docker.internal, DNS and NAT, with no virtual switch and no admin rights. More

Settings and daemon.json. hyperbutler config sets memory, CPUs and disk size; a daemon.json reaches dockerd (registry mirrors, insecure registries…) and applies without restarting the VM. More

The window. hyperbutler gui shows the engine, containers by Compose project with their logs, storage, settings and troubleshooting, in English or Korean. It makes no network requests. docs/gui.md

AI tools (MCP). hyperbutler mcp lets an MCP client (your editor's AI assistant) read status, containers, logs and disk use. Starting, stopping and deleting need flags you add, and what it may run is fenced in. docs/mcp.md

Moving from Docker Desktop. hyperbutler import --from-desktop copies images and volumes over. docs/tools.md

When something is wrong. hyperbutler doctor checks every prerequisite and says how to fix it (--fix repairs what it may); hyperbutler diagnose packs a redacted report. More

Design decisions are in docs/adr; how releases are built and checked is in docs/release.md.

Is this Docker? It runs Docker's own engine (dockerd, containerd) in a Linux VM and speaks the Docker API, so Docker's tools work with it. It is not made by Docker, Inc.

How is it different from Docker Desktop? Lighter (see the table), no WSL, gives disk and memory back without tuning, no account, free at any company size. Docker Desktop has Kubernetes, Windows containers and extensions; hyperbutler does not.

Windows containers? Windows 10? No to both: Linux containers on Windows 11 only.

Do I need to be an administrator? Once, for the MSI. After that, no: the broker service it installs starts your VM for you (since v0.1.0-preview.2; preview.1 added you to Hyper-V Administrators instead, and upgrading takes that membership out again). The zip, without the service, needs Hyper-V Administrators membership (install guide).

Why Go? The container stack (containerd, moby, gVisor's network stack) is Go, and the cost is measured: the engine idles at about 18 MB. Leaks are design bugs in any language, so every package's tests fail on a leaked goroutine and a 24-hour soak gates releases. ADR 0003

Issues and pull requests are welcome: see CONTRIBUTING.md. Security issues: SECURITY.md.

hyperbutler is Apache-2.0. The release also contains a Linux guest image with GPL-2.0 components (the Linux kernel, BusyBox and others); their corresponding source is published with each release, and SOURCE-OFFER.txt and THIRD-PARTY/ list them.

Docker is a trademark of Docker, Inc. hyperbutler is not affiliated with or endorsed by Docker, Inc. or Microsoft.