How we brought multimedia search to Dropbox Dash

This post details the engineering behind adding multimedia search (images, video, audio) to Dropbox Dash. It covers the challenges of storage and compute costs, relevance, and responsiveness for media files. The solution involves indexing lightweight metadata (file path, title, EXIF) using the Riviera framework, backfilling the index with raw content for preview generation, and optimizing storage. At query time, it matches input against metadata, applies custom logic for geographic references, and tokenizes camel case/hyphenated strings. Previews are generated just-in-time on the read path to balance latency and resource efficiency.