Bitcoin testnet4 · Spark REGTEST · no mainnet paths
Creative Bitcoin
📷 Photography · photo metadata

Chain-Verified EXIF II

Verify and store immutable EXIF data onchain without wallet or gas barriers.

Spark sats paywall· instant sats payments
Section · Onchain

The primitive.

full primer →

Photographers pay a few sats over Spark (Bitcoin L2) via a single Privy-signed transfer to unlock the photo metadata; settlement is instant and the merchant confirms via getBalance.

Why this primitiveA Spark sats transfer settles in under a second and is Bitcoin-native — perfect for gating this content behind a one-click, low-friction micropayment.

Kernel
a 'pay N sats on Spark to unlock' gate — the user signs a Spark transfer via Privy, the merchant's wallet observes the transfer via Spark's getBalance/getTransfers, and the endpoint releases the payload
Drives the UI as
a 'pay 100 sats to unlock' button that returns the Spark tx id, the merchant confirmation, and settles instantly
Appendix · Secrets

Required keys.

PRIVY_APP_ID
Privy dashboard → your app. Configure with chainType 'spark' to mint Bitcoin L2 wallets on sign-in.
open ↗
PRIVY_APP_SECRET
Server-side. Required for the merchant Spark wallet to observe incoming sats transfers via the Privy RPC.
open ↗
PINATA_JWT
Pins images / JSON / manifests to IPFS.
open ↗

Add these in your Lovable project under Settings → Secrets before pasting the prompt below.

Appendix · Mega-prompt

The build prompt.

Paste into a fresh Lovable project — it carries its own feature spec, code, setup and checklist. read the build strategy →

loading the build spec…
Open in Lovable ↗mempool.space testnet4 ↗
Appendix · Market

Market sizing.

TAM
$2.4B
photo metadata verification
SAM
$400M
immutable photo data tools
SOM
$11M
onchain EXIF verification

Indicative figures for hackathon pitches — refine with your own research before raising.

See also

Adjacent entries.

photo metadata
Gasless Metadata Tags
Add and sync photo metadata onchain without gas fees or wallet complications.
photo metadata
Chain-Verified EXIF
Verify and store immutable EXIF data onchain without wallet or gas barriers.
photo sharing
Gasless Gallery II
Seamlessly share photos onchain with no gas fees for your audience and collaborators.
photojournalism
NFT Photo Stories II
Create and share onchain photo stories with built-in provenance and no wallet setup hassle.