Bitcoin testnet4 · Spark REGTEST · no mainnet paths
Creative Bitcoin
🎥 Videography & Film · subtitle generation

AutoSubtitle Mint II

Generate and store verified subtitles onchain to guarantee transcript authenticity.

Privy Spark sign-in· bitcoin wallet UX
Section · Onchain

The primitive.

full primer →

Videographers sign in with Google through Privy — no seed phrase, no wallet extension — and Privy mints them a Spark (Bitcoin L2) wallet plus a Bitcoin testnet deposit address in one flow.

Why this primitiveA Privy Spark embedded wallet lets creators sign in with Google and receive a Bitcoin L2 address in one click — no seed phrase, no browser extension.

Kernel
Privy embedded wallet with chainType 'spark' — Google / email sign-in mints a Bitcoin testnet address plus a Spark (Bitcoin L2) address in one flow, no seed phrase, no extension
Drives the UI as
a one-click 'Sign in with Google' that drops the user into the app with a copy-able Spark address and a testnet BTC deposit address
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
$1.1B
video accessibility tools
SAM
$110M
subtitle generation software
SOM
$14M
content creators needing verified transcripts

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

See also

Adjacent entries.

subtitle generation
AutoSubtitle Mint
Generate and store verified subtitles onchain to guarantee transcript authenticity.
edit history
EditVersion Ledger II
Track and verify every edit version of a video project transparently on the blockchain.
licensed assets
ClipLicense Swap II
Facilitate secure, onchain licensing and transfer of video clips between creators.
color grading
ColorGrade NFT II
Create and trade unique onchain color grade presets as NFTs for creative reuse.