A digression thanks to Sal Rashid who’s exploring WASM filters w/ Envoy. The documentation is sparse but: How to write WASM filters for Envoy… There is a Rust SDK but it’s not documented: proxy-wasm-rust-sdk I found two useful posts by Rustaceans who were able to make use of it: Extending Envoy with WASM and Rust Extending Istio with Rust and WebAssembly Here’s my simple use of the SDK’s examples. wasme curl -sL https://run.