Perplexity built Photon, an in-house retrieval and ranking engine designed to replace an open-source platform that faced scaling costs, tail latency, and recovery time constraints.

Photon powers Perplexity's search pipeline and a new fast preset for its Search API, achieving single-search-call latency of 160 ms at p50 and 230 ms at p95, and reducing estimated model-plus-search cost per task by 68% across six public benchmarks while maintaining comparable task quality.