A brief history of WASM/WASI and then dive into the upcoming Sliver v1.6 release, which includes a prototype feature that allows operators to encode C2 traffic using WASM-based callback functions. These WASM-based encoder functions can be dynamically loaded at runtime by both the server and the implant. We’ll discuss the limitations of the technology (e.g. performance) , how the network encoder interface works, as well as potential future applications of the technology.