enzo comes at it from the other side. no local model setup at all, you paste your own api key (openrouter, groq, gemini, whatever you already have) and requests go from your instance straight to that provider. i built it cause I was already paying for provider keys and wanted everything on my own box instead of scattered across 5 different chat apps.
the other difference is it's more an agent workspace than a chat ui. stuff like "scan my unread gmail and draft replies" or "find me a slot on my calendar next week" works right after oauth — you don't go hunting for community plugins or wiring tools yourself. it also generates full-stack web apps and serves them from the same instance, which openwebui doesn't really do.
and it's plain apache 2.0 (openwebui moved to a custom license with branding requirements a while back, which annoyed a bunch of people at the time)
so yeah same shelf, different product imo. got a gpu and want local models then openwebui. already have api keys and want the thing to actually go do stuff for you then enzo