WebAssembly is a general-purpose low-level virtual machine. It was the first programming language to be introduced to the Web since JavaScript, and has since been adopted in many other environments, such as edge and cloud computing, mobile computing, blockchains, and embedded systems. Unusually for an industrial language, WebAssembly’s normative specification is stated fully in terms of a pen-and-paper formal semantics. In addition, multiple mechanisations of this semantics have been created and used to prove the soundness of the WebAssembly type system.

The rigor of WebAssembly’s semantics presents new opportunities for researchers in Programming Languages to apply their craft to a widely-used industry technology. This WebAssembly Workshop (WAW) intends to create a space where new ideas for such research can be brainstormed, and where ongoing research work related to WebAssembly can be discussed, critiqued, and iterated on. We also hope to familiarize researchers with the successes and challenges of WebAssembly’s design and specification from an industrial point of view, thereby empowering them to influence the future direction of the language.

After the success of the first edition of WAW at POPL 2024, we are introducing a new open Call for Presentations alongside this year’s invited speakers.

Call for Presentations

We invite the submission of abstracts and extended abstracts describing a WebAssembly-related topic for presentation at the workshop. Since this workshop will not publish formal proceedings, we welcome submissions based on prior and ongoing work.

Submissions may be made either in text or PDF form through our HotCRP site (https://waw2025.hotcrp.com/). Text submissions are limited to 500 words, while PDF submissions may be up to 2 pages in length, not including references. We encourage authors to use a standard ACM template for PDF submissions. The review process will be lightweight — after the review period authors will receive a single feedback comment on behalf of the Program Committee, confirming the acceptance status of their submission. While we can support a limited number of remote speakers, the selection process will favour submissions that can be presented in-person.

Chris Fallin

Chris Fallin is a senior architect at F5, where he works on WebAssembly-related compiler tooling, continuing work he has done at Fastly and Mozilla on SpiderMonkey, the Cranelift JIT compiler (tech lead for three years), and the Wasmtime virtual machine. Prior to those positions, he has worked at Google and Intel. He completed his PhD in compilers at Carnegie Mellon University.

Deepti Gandluri

Deepti is an engineer on the Google Chrome team leading WebAssembly standardization efforts. She has previously co-chaired both the WebAssembly Community Group and the Working Group. Deepti works on V8, Chrome’s JavaScript engine, and has championed and instigated compute extensions to the WebAssembly standard, motivated by decreasing the performance gap between WebAssembly and native application implementations. Prior to her work at Google, Deepti wrote simulation tools for pre-silicon validation at Intel.

Deian Stefan

Deian is an Associate Professor of Computer Science and Engineering at UC San Diego, where he co-leads the Security and Programming Systems groups. His research lies at the intersection of security and programming languages; he is particularly interested in building secure systems that are deployed in production. He is a co-founder of Cubist, a security startup shipping a high-assurance key management platform, and a board director of the Bytecode Alliance. Previously a co-founder of Intrinsic, a runtime security startup acquired by VMware in 2019.