June 2026: Envoy proxy wasm stability and tooling improvements. Delivered two major, code-level contributions with targeted validation to improve runtime stability, portability, and wasm build reliability. 1) Dependency updates for ProxyWasm/Wasmtime in envoy proxy: Upgraded proxy_wasm_cpp_host and wasmtime from v24.0.0 to v42.0.1 to fix unimplemented wasi hostcalls and endianness conversions on big-endian platforms; tests executed with Bazel to ensure compatibility. Commit: 9c53b0084139ea6d800d92f0bdd7a47bec64e3f5. 2) Migrate wee8_compile to the Proxy-Wasm serialization API for improved AOT wasm compilation: Migrated the AOT build script to leverage the official serialization API, achieving better alignment with current standards and more reliable wasm module compilation. Commit: 80d4341b91fdd262d8012e9911f06432fa65989e.

February 2026 (2026-02): Implemented deferred CEL matching for request and response headers in envoyproxy/envoy, enabling CEL expressions to evaluate across both paths and support toggling of response-only filters. This included a refactor to upgrade InputMatchers to a MatchResult, allowing the CEL matcher to bubble up insufficient data instead of silently failing, and groundwork for cross-path header-based filter control. Added unit tests and release notes to ensure reliability and clear change management.

August 2025: Delivered Flexible Composite Filter for Response Path Mutation in docker/envoy, enabling insertion of filters on the response encode path to mutate response bodies based on headers and content types. This feature supports expensive filters like ext_proc and includes updates to core filter logic, changelogs, and documentation, along with integration tests to validate end-to-end behavior.

July 2025 Dev Monthly Summary for envoyproxy/envoy-openssl: Delivered a security-focused V8 upgrade and WASM runtime compatibility improvements. Implemented an authoritative update to V8 13.8.258.26 with patches for proxy_wasm_cpp_host, enabling better security posture and Wasm compatibility. No major bugs identified this month; changes were focused on dependency updates and stability. This establishes a stronger foundation for upcoming WASM-enabled features and long-term stability.