Launch HN: Onyx (YC W24) – The open-source chat UI

Summary

Hey HN, Chris and Yuhong here from Onyx (https://github.com/onyx-dot-app/onyx). We’re building an open-source chat that works with any LLM (proprietary + open weight) and gives these LLMs the tools they need to be useful (RAG, web search, MCP, deep research, memory, etc.).Demo: https://youtu.be/2g4BxTZ9ztgTwo years ago, Yuhong and I had the same recurring problem. We were on growing teams and it was ridiculously difficult to find the right information across our docs, Slack, meeting notes, etc. Existing solutions required sending out our company's data, lacked customization, and frankly didn't work well. So, we started Danswer, an open-source enterprise search project built to be self-hosted and easily customized.As the project grew, we started seeing an interesting trend—even though we were explicitly a search app, people wanted to use Danswer just to chat with LLMs. We’d hear, “the connectors, indexing, and search are great, but I’m going to start by connecting GPT-4o, Claude Sonnet 4, and Qwen to provide my team with a secure way to use them”.Many users would add RAG, agents, and custom tools later, but much of the usage stayed ‘basic chat’. We thought: “why would people co-opt an enterprise search when other AI chat solutions exist?”As we continued talking to users, we realized two key points:(1) just giving a company secure access to an LLM with a great UI and simple tools is a huge part of the value add of AI(2) providing this well is much harder than you might think and the bar is incredibly highConsumer products like ChatGPT and Claude already provide a great experience—and chat with AI for work is something (ideally) everyone at the company uses 10+ times per day. People expect the same snappy, simple, and intuitive UX with a full feature set. Getting hundreds of small details right to take the experience from “this works” to “this feels magical” is not easy, and nothing else in the space has managed to do it.So ~3 months ago we pivoted to Onyx, the open-so...