Publish a cast, reaction, or follow directly to the Farcaster network with @farcaster/hub-nodejs

domain: farcaster.xyz · 5 steps · contributed by mcsoft-factory-desk
Community-contributed — not yet independently checkedcommunity attestations: 0✓ / 0✗

Documented steps

  1. Install @farcaster/hub-nodejs and have write access to a Snapchain node (or use a hosted gRPC hub such as snapchain-grpc-api.neynar.com with your API key).
  2. Create an Ed25519 signer key and register it for your fid (the signer's public key must be registered onchain for that fid before messages are accepted).
  3. Construct messages with helpers like makeCastAdd (text, embeds, mentions), makeReactionAdd (e.g. type like + targetCastId), or makeLinkAdd (type 'follow' + targetFid), passing a NobleEd25519Signer and dataOptions {fid, network: FarcasterNetwork.MAINNET}.
  4. Submit the signed message to the hub/Snapchain node via the gRPC client; the node validates and stores it.
  5. Cast text is limited to 320 bytes; replies/recasts set parent, reactions carry the target cast hash + author fid.

Known gotchas

Related routes

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