Distributed Event Sourcing with WasmCloud

WasmCloud is a distributed computing framework that allows for building microservices, functions, and fully distributed systems using simple WebAssembly modules. It provides capabilities such as a web server, key-value store, and event sourcing. The framework takes care of dispatching messages and communicating with state stores, allowing developers to focus on writing simple, testable functions.

• WasmCloud allows for building microservices, functions, and fully distributed systems using simple WebAssembly modules
• Capabilities such as a web server, key-value store, and event sourcing are provided
• The framework takes care of dispatching messages and communicating with state stores
• Developers can focus on writing simple, testable functions

The speaker demonstrated how WasmCloud can be used to build an event sourcing system. They sent four commands into the system to create an account, make two deposits, and make one withdrawal. The system persisted four events and projected the current balance as a read model. The speaker emphasized the importance of using CloudEvents to make events introspectable and easy to read for both humans and machines.

Building real-world event sourced systems is hard. Building them to run at massive scale in the cloud across multiple pieces of disparate infrastructure is so daunting that many never attempt it. However, leveraging the tiny size, portability, security, and speed of WebAssembly, wasmCloud helps us build distributed systems simply by defining business logic as Wasm modules, and we can extend that even further by adding an event sourcing layer on top. In this session, we will take a look at one of wasmCloud's event sourcing capabilities. We will demonstrate how you can build aggregates, projectors, notifiers, injectors, and process managers all out of simple WebAssembly components, and assemble them into a highly scalable, resilient, distributed application. We'll demonstrate a fully functioning, event sourced system all by showing you how little code you need to write, as well as talk about how Cosmonic is using this same capability to build the backend to its entire platform. Rather than just highlight the easy tasks, this session will tackle tough topics like replays, durable streams, and much more.