Introducing the Docker+Wasm Technical Preview

The is now available! Wasm has been producing a lot of buzz recently, and this feature will make i

The is now available! Wasm has been producing a lot of buzz recently, and this feature will make it easier for you to quickly build applications targeting Wasm runtimes. As part of this release, we’re also happy to announce that Docker will be joining the as a voting member. The Bytecode Alliance is a nonprofit organization dedicated to creating secure new software foundations, building on standards such as WebAssembly and WebAssembly System Interface (WASI). , often shortened to Wasm, is a relatively new technology that allows you to compile application code written in over 40+ languages (including Rust, C, C++, JavaScript, and Golang) and run it inside sandboxed environments. The original use cases were focused on running native code in web browsers, such as , , and . In fact, saw a when converting their web-based DNA sequence quality analyzer to Wasm. And Disney built their on top of Wasm! The benefits in the browser are easy to see. But Wasm is quickly spreading beyond the browser thanks to the (WASI). Companies like , , , and support using Wasm for running code at the edge, and is building a platform to run Wasm microservices in the cloud. At Docker, our goal is to help developers bring their ideas to life by conquering the complexity of app development. We strive to make it easy to build, share, and run your application, regardless of the underlying technologies. By making containers accessible to all, we proved our ability to make the lives of developers easier and were recognized as the . We see Wasm as a to Linux containers where developers can choose which technology they use (or both!) depending on the use case. And as the community explores what’s possible with Wasm, we want to help make Wasm applications easier to develop, build, and run using the experience and tools you know and love. Ready to dive in and try it for yourself? Great! But before you do, a couple quick notes to keep in mind as you start exploring: WASM is no longer in beta. Download to start using it. Yes! This is an early technical preview and we’re still working on making the experience as smooth as possible. But here are a few things you should be aware of: We’re glad you asked! First off, we need to remind you that since this is a technical preview, things may change quite rapidly. But here’s how it currently works. After installing the preview, we can run the following command to start an example Wasm application: Since a few of the flags might be unfamiliar, let’s explain what they’re doing: After the image is pulled, the runtime reads the of the image to locate and extract the Wasm module. The module is then loaded into the Wasm runtime, started, and networking is configured. We now have a Wasm app running on our machine! This particular application is a simple web server that says “Hello world!” and echos data back to us. To verify it’s working, let’s first view the logs. We can get the “Hello world” message by either opening to or using curl. And our response will give us a Hello world message: To send data to the echo endpoint, we can use curl: And we’ll see the data sent back to use in the response: To remove the application, you can remove it as you do any other Docker service: The new integration means you can run a Wasm application alongside your Linux containers (even with Compose). To learn more, ! Another great question! Wasm is rapidly growing and evolving, including exploration on how to support , , and more. There are also many still-to-tackle challenges, including shortening the developer feedback loop and possible paths to production. So and then let us know your thoughts or feedback on . We’d love to hear from you!