How Docker+Wasm Is Transforming Container Runtime with WebAssembly

Docker announced the first technical preview of Docker+Wasm, a new integration that lets developers quickly build applications for the Wasm runtime, and confirmed its membership as a voting member of the Bytecode Alliance.

Bytecode Alliance, founded by Mozilla, Fastly, Intel, and Red Hat, promotes WebAssembly standardization and is actively advancing the WebAssembly System Interface (WASI) to enable safe access to files, network, and memory outside browsers.

Docker Engine continues to use the containerd runtime but adds a new containerd shim that replaces the standard runC with the WasmEdge runtime. This shim extracts Wasm modules from OCI artifacts and runs them with WasmEdge.

WasmEdge promises faster startup times, smaller application sizes, and higher execution speed compared to traditional Linux containers.

Docker co‑founder Michael Irwin said that Wasm is a complementary technology to Linux containers, allowing developers to choose the best solution or combine both, and that familiar tools will make Wasm apps easier to develop, build, and run.

To try the preview, run the following command:

docker run -dp 8080:8080 --name=wasm-example --runtime=io.containerd.wasmedge.v1 --platform=wasi/wasm32 michaelirwin244/wasm-example

Parameter explanations: --runtime=io.containerd.wasmedge.v1 – tells Docker Engine to use the Wasm containerd shim instead of the standard Linux container runtime. --platform=wasi/wasm32 – specifies the Wasm architecture, allowing a single image to run on any platform; the Wasm runtime handles the final translation to machine instructions.

Download the Docker Desktop technical preview for your platform:

macOS Apple Silicon: https://dockr.ly/3sf56vH

macOS Intel: https://dockr.ly/3VF6uFB

Windows AMD64: https://dockr.ly/3ShlsP0

Linux Arm64 (deb): https://dockr.ly/3TDcjRV

Linux AMD64 (deb): https://dockr.ly/3TgpWH8 (rpm: https://dockr.ly/3eG6Mvp , tar: https://dockr.ly/3yUhdCk )

Note that Docker+Wasm is still in early technical preview and should not be used in production environments due to possible changes or removal in future releases.

For more details, see the official documentation: https://docs.docker.com/desktop/wasm/