Show HN: Capsule – Single-file web apps that save their data into SQLite(withcapsule.app)
334 points by bashtian 22 hours ago | 141 comments
tl;dr: Capsule bundles a web app's UI, schema, and SQLite data into a single portable .capsule file that can be shared like a PDF and opened via a cross-platform host player (macOS, Windows, Linux, with iOS/Android planned). Apps are generated and iterated via AI prompts or MCP tools, run fully offline, and keep all data local with no accounts or cloud dependencies.
HN Discussion:
  • Modern browser APIs like File System Access and OPFS already enable this without a separate host player
  • Requiring a downloaded host player defeats the purpose since you could just send the app directly
  • Bundling state into a shareable file creates awkward sync/update workflows compared to web hosting
  • This is a great solution for sharing AI-generated apps with embedded data
  • Others are building or have built similar single-file portable app concepts, validating the idea