Showcase · Vol. 02

Working demos, all on Bitcoin.

Reference builds from the prompt library. Each demo runs on Bitcoin testnet4 or Spark REGTEST — no EVM, no gas token, no MetaMask.

Dance · OP_RETURN provenanceLive ↗

Choreo Ledger

Timestamp original choreography on Bitcoin. Paste a title or hash, we broadcast a testnet4 tx with the SHA-256 in OP_RETURN, and mempool.space becomes your proof.

https://mempool.space/testnet4

Payments · Spark satsLive ↗

Sats Paywall

Pay 100 sats on Spark (Bitcoin L2) to unlock a protected endpoint. Sign in with Google via Privy — no seed phrase — the transfer settles instantly and the merchant confirms via getBalance.

Merchant wallet: app-owned Spark wallet on REGTEST