"WebAssembly System Interface Design and Implementation"
"WebAssembly System Interface Design and Implementation" is an authoritative guide to the foundational principles, technical architecture, and real-world application of WASI—the WebAssembly System Interface. Beginning with a deep dive into WebAssembly fundamentals, the book systematically unpacks the virtual machine's architecture, execution model, type system, and the mechanics of module interaction. It provides clear, practical insights into topics such as linear memory management, sandboxing, and the security model at the host-guest boundary, as well as detailed comparisons of leading language toolchains and runtime implementations.
The book progresses to explore the historical context and driving motivations behind WASI, contrasting its capability-based security approach with traditional POSIX systems. Readers learn how WASI's unique abstraction reshapes system primitives, emphasizing modularity, explicit capability granting, and secure sandboxing. The core WASI specification is dissected in detail, including the design and extension of system calls, virtualized I/O, process management, error handling, and type-safe multi-language interface bindings, providing architects and system implementers with actionable guidance for robust and extensible WASI deployments.
In its advanced chapters, the book examines implementation strategies for hosts and runtimes, techniques for performance optimization, debugging, and emerging models for multithreading, networking, and device access. A dedicated focus to security, privacy, formal verification, and cross-platform portability ensures that developers understand how to build resilient and future-proof WebAssembly applications. Through real-world case studies—spanning serverless computing, IoT, browser environments, and more—the book illustrates best practices and pragmatic lessons, while concluding with forward-looking insights into WASI's evolving ecosystem, research frontiers, and opportunities for open-source and community-driven innovation.
