Wasmtime is a fast, secure, and standards-compliant WebAssembly runtime. The latest v26.0 release includes enhancements such as implementation of the “table64” extension, a new wasmtime completion subcommand, ARM64 Windows support, and more.

Wasmtime is a lightweight WebAssembly runtime that is fast, secure, and standards-compliant. Today’s release of Wasmtime v25.0 brings enhancements including extended constants, WASI 0.2.1 support, and user stack maps.

As part of implementing the WebAssembly garbage collection proposal in Wasmtime, which is an ongoing process, we’ve overhauled the stack map infrastructure in Cranelift. This post will explain what stack maps are, why we needed to change them, and how the new stack maps work.

The Bytecode Alliance is pleased to invite you to the next installment in our ongoing Plumbers Summit event series, each designed to bring our members and community contributors together to help set strategic direction and plan efforts for the coming year. Our next Summit will be September 26 and 27, 2024 at the Microsoft Visitor Center in Redmond, Washington. Seating for the in-person session is limited but the event will be live streamed online to support full remote participation.

If you’re a .NET/C# developer, componentize-dotnet makes it easy to compile your code to WebAssembly components using a single tool. This Bytecode Alliance project is a NuGet package that can be used to create a fully AOT-compiled component from a .NET application—giving .NET developers a component experience comparable to those in Rust and TinyGo.

Welcome to the Bytecode Alliance blog. 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).

We are aware that the account responsible for the recent XZ backdoor contributed a documentation-only pull request to Wasmtime, however Wasmtime’s safety remains intact. We have reviewed the pull request in detail and confirmed that it only modified a single markdown file, and contained no changes to source code, build systems, or binaries. Furthermore, the documentation was not altered in such a way that it could trick unsuspecting readers into sabotaging themselves.

On February’s community stream, Bytecode Alliance Technical Steering Committee Director Bailey Hayes and Consulting Executive Director David Bryant provided updates on individual projects, SIGs, and direction for the ecosystem.

We’re happy to announce the 1.0 release of Jco: a native Javascript WebAssembly toolchain and runtime built for WebAssembly Components and WASI 0.2 1. Jco can natively run Wasm Components inside of Node.js, making it easy to take libraries written in different programming languages and execute them using the Node.js runtime. And by implementing the entirety of the WASI 0.2 API surface, those components can access the network, filesystem, and other system APIs available in the Node.js runtime. WebAssembly Components are an extension to WebAssembly to create strongly typed interfaces between different programs. WASI 0.2 is a re-work of the “WebAssembly System Interfaces” based on WebAssembly Components. The previous version of WASI was not based on components, and as a result was rather limited in what it could express. ↩

Last week, the Bytecode Alliance Plumber’s Summit gathered in Raleigh, NC to map the road ahead for the WebAssembly ecosystem. You can read a summary of the summit’s first day on the Bytecode Alliance blog or watch the full recording on YouTube. While much of the second day was conducted in breakout sessions, some consistent themes ran through many of those conversations, including the implementation of async and developer experience.