William Casarin, known as jb55, is best known for Damus, the iOS Nostr client that helped make Nostr tangible for mainstream mobile users.
Public role in Nostr
William Casarin (jb55) is included here because of a visible public role in the Nostr universe: Damus creator and Bitcoin-Nostr client developer. The profile is intentionally focused on ecosystem work rather than private biography.
- Damus. iOS Nostr client with social feed, zaps, media and relay transparency.
- Notedeck. Multiplatform Nostr client work for desktop and Android.
- NostrDB and Notecrumbs. Infrastructure around local event storage and note rendering.
Why this matters for the Nostr archive
Nostr is easier to understand when the protocol is connected to real builders and products. The ecosystem is not one company. It is a mesh of people building clients, relays, libraries, signers, wallets, media tools, community infrastructure and funding channels.
Crays relevance
For Crays, Damus is an important proof that Nostr can feel like a normal social product while still keeping keys, relays and Lightning close to the surface.
How to keep this profile accurate
Use the source links below as the verification layer. Future edits should update roles, projects and dates from primary project pages, public repositories or funding announcements instead of copying unsourced summaries from random reposts.