YC-backed Moss is hiring for the SDK layer of real-time AI search

YC-backed startup Moss is hiring a senior SDK engineer to build the integration layer for its real-time semantic search platform, which claims sub-10 ms retrieval for conversational AI. The company has published traction figures including 380,000+ package installs and 5M+ voice minutes served across 100+ countries, positioning the SDK as critical for developer adoption and latency-sensitive voice agents.

Sri Raghu Malireddi https://www.linkedin.com/in/r4ghu?ref=runtimewire is hiring a senior or staff SDK engineer for Moss https://www.ycombinator.com/companies/moss/jobs/52LnqLQ-software-engineer-sdk?ref=runtimewire , the YC-backed semantic search startup built around a narrow but consequential claim: conversational AI breaks when retrieval is too slow. The YC job listing https://www.ycombinator.com/companies/moss/jobs/52LnqLQ-software-engineer-sdk?ref=runtimewire , visible on July 10, describes Moss as a "real-time semantic search layer for conversational AI" and offers $60,000 to $300,000 in salary, plus 0.10% to 0.50% equity. The role is full-time, tagged as engineering and embedded systems, open in San Francisco or remote, requires 6+ years of experience, and says Moss will sponsor visas. This is not a general AI application job. Moss wants someone to own SDK architecture across JavaScript/TypeScript, Python, Swift, Android, Elixir, C, and the Rust core they bind to. The listing asks for systems engineering experience across memory management, concurrency, FFI, package distribution, build systems, cross-platform development, WebAssembly, mobile runtimes, edge environments, browser internals, search, databases, AI infrastructure, compilers, and developer tooling. That breadth says Moss is trying to win distribution at the layer where developers first touch infrastructure. As the listing puts it, the SDKs are "how every one of those developers meets Moss," and the work includes shrinking bundle size, lowering cold-start and query latency, tightening cross-platform parity, improving developer ergonomics, and making integration effortless across browsers, servers, mobile devices, edge runtimes, and embedded environments. What Moss says it does Moss describes itself as a real-time semantic search layer for conversational AI, delivering sub-10 ms retrieval directly in the browser, at the edge, on-device, or in the cloud. You can read more on the Moss homepage https://www.moss.dev/?ref=runtimewire and in the YC listing above. The numbers are company-supplied, and they matter Moss gives several traction figures in the YC job listing: deployed across 100+ countries, 5M+ real-time voice minutes served, supporting enterprises that serve 3,000+ of their own end customers, and 380,000+ package installs. These are Moss-published numbers on a hiring page rather than audited metrics, and Moss does not disclose revenue, headcount beyond the listing context, named customers in the listing, valuation, total funding, or round terms beyond YC backing. Why this hire is strategically important Voice agents have less tolerance for infrastructure delay than chat interfaces. A chatbot can hide latency behind a typing indicator; a phone agent that pauses at the wrong moment feels broken. If Moss’s bet is that retrieval cannot live several hops away from the agent, then the SDK layer becomes the product: the install has to be quick, the runtime has to fit each platform, the bindings have to behave consistently, and the latency claim has to survive real devices. That is a hard engineering problem, and Moss is hiring as if the hard part sits below the demo.