Comment by sparacha

Two things

1/ Arch builds on Envoy so that we don't re:invent all the HTTP(s)/TCP level capabilities needed in a modern gateway for applications. So in that sense, we agree with you that it should "extend" something vs. rewriting the whole stack. There are several security and robustness guarantees that we borrow from Envoy as a result of this. To be more specific, a lot of Arch's core implementation today is an Envoy filter written in Rust.

1/ Arch's core design point is around the handling and processing of prompts, which we believe are nuanced and opaque user request that require secure handling, intelligent routing, robust observability, and integration with backend (API) systems for personalization – all outside business logic. This requires the use of models and LLMs that are fast, cheap and capable to help developers stay focused on application features. For example, Arch uses (fast) purpose-built LLMs for jailbreak detection, converts prompts into API semantics for personalization, and (eventually) automatically routing to the best outbound LLM based on the complexity of a prompt to improve the cost/speed of an app.

We believe #2 will continue to be different and evolve further away from traditional API/HTTP routing that it will require constant invention and work to make the lives of developers easy.

Hope this helps!