Coracle

Coracle is a nostr web client built by Hodlbod. It started as a social feed reader but has grown to cover group chat, direct messages, communities, marketplaces, and classifieds. The client runs in the browser and works across desktop and mobile.

Much of nostr's novelty has to do with keys and digital signatures. But focusing on the cryptographic aspects is, to me, actually something of a distraction. The important thing to realize is that digital signatures make relays possible.

—Hodlbod

Consequently, Coracle puts the most effort into relay handling. Users can choose which relays receive a given note, and the outbox model figures out where to fetch posts from based on who you follow. Smarter fallback behavior keeps timelines loading even when individual relays go down. Negentropy-based sync makes refreshing feeds faster by only pulling what changed. A restored global feed gives newcomers an easy way to browse the wider network.

Hodlbod also works on relay infrastructure directly. He proposed and implemented NIP-43 for relay membership lists and built zooid, a relay that uses them. Combined with NIP-86 for relay admin controls, these features let relays state who they serve and what content they host.

Why fund it?

Coracle is one of the longer-running nostr clients and has been a testing ground for relay-related protocol improvements. Hodlbod ships NIP implementations in Coracle, tests them in production, and feeds results back into the spec process. Daniele contributes UX and reliability work.

The project has also produced Welshman, a library extracted from Coracle that other nostr projects can use.

OpenSats has been supporting Coracle since the first wave of nostr grants in July 2023. Hodlbod later received a long-term support grant.

What's next?

Coracle itself is in maintenance mode while Hodlbod focuses on Flotilla, a group chat client that treats relays as first-class citizens for access control and content policies. Active development includes voice rooms, a relay hosting platform, and Pomade, an email/password login protocol for normie-friendly key management. The Welshman library that powers both clients continues to see major work, including a store rewrite for performance and improved outbox relay selection.

For a detailed look at earlier progress, see the Advancements in Nostr Clients impact report.