Live on Starknet Sepolia · Re{define} Hackathon 2026

Prove your BTC.
Never move it.

BitProof is the first trustless BTC Proof-of-Reserves primitive for Starknet. Sign once. Get a credential. Access all of DeFi. Zero bridges. Zero custodians.

View Source ↗
300k+BTC locked in custodians
$2.5BLost to bridge hacks
1 fn()To integrate any protocol
0BTC ever moved or bridged
The Problem

Bitcoin holders are
locked out of DeFi.

Every existing solution forces you to trust someone or move your BTC. We built the alternative.

01 / 05🌉
Bridge Hacks Cost Billions

Every bridge is a honeypot. $2.5B stolen from bridges in 2022 alone. Wormhole. Ronin. Nomad. All bridges.

❌ Bridge your BTC → custodian risk
✓ BitProof → zero bridging
02 / 05🔒
Wrapped BTC = Blind Trust

WBTC requires trusting BitGo as a centralized custodian. One hack, one regulatory action, your BTC is gone.

❌ WBTC → trust BitGo
✓ BitProof → cryptographic proof
03 / 05💀
$1T Sits Idle

Bitcoin holders can't access DeFi yield, lending, or liquidity without giving up custody. The market is starving for this primitive.

❌ Sell BTC or lose DeFi access
✓ Hold BTC + use DeFi
04 / 05🔧
Protocol Integration Nightmare

Every lending protocol wanting BTC collateral had to build their own bridge. Months of work, millions in audits.

❌ Build custom bridge per protocol
✓ verify_btc_holding() — 1 line
05 / 05👁️
Public Collateral = MEV Target

On-chain collateral positions are visible. Liquidation bots front-run you. Your position is their opportunity.

❌ Public collateral → MEV losses
✓ Credential only — amounts private
₿
BitProof
The primitive that solves all five. One signature. One proof. The entire DeFi ecosystem unlocked.
How It Works

Four steps. One primitive.

From Bitcoin wallet to Starknet DeFi — the full flow in under 60 seconds.

01
Connect Xverse

User connects their Bitcoin wallet. App reads their BTC address and balance via Mempool API. Nothing moves.

sats-connect
02
Sign Message

User signs a binding message with their BTC private key using ECDSA over secp256k1. Standard Bitcoin signing.

ECDSA / secp256k1
03
Verify On-Chain

Cairo contract verifies the signature using Starknet's native secp256k1 precompile. Zero external dependencies.

verify_eth_signature()
04
Credential Issued

BTCCredential stored on Starknet. Any protocol queries it in one function call. Loan approved. DeFi unlocked.

verify_btc_holding()
The SDK Primitive

Any protocol.
3 lines.

BitProof isn't an app — it's infrastructure. Install our SDK and add BTC collateral to your protocol in an afternoon. No bridges to build. No audits to run. Just one function call.

✓ Works with Vesu, Ekubo, Nostra, any Starknet protocol
✓ Native secp256k1 — no external ZK circuit needed
✓ Gas: ~$0.001 per verification on Starknet
✓ Open source, MIT licensed
your-protocol.js
// Install: npm install bitproof-sdk
 
const { BTCProofSDK } = require('bitproof-sdk');
 
// Initialize with deployed oracle
const sdk = new BTCProofSDK(
  '0x07f5fc8...d890a'
);
 
// ← The entire primitive, one line
const eligible = await sdk.verify(
  userAddress,
  0.1   // min 0.1 BTC
);
 
if (eligible) {
  approveLoan(user); // 🎉
}
Competitive Analysis

Why BitProof beats everything else.

ProjectMarket CapCustodianBridge Needed?BTC Moves?Risk
WBTC (BitGo)$8.18B❌ BitGoYESYESCustodial
cbBTC (Coinbase)$6.1B❌ CoinbaseYESYESCustodial
BTCB (Binance)~$5B❌ BinanceYESYESCustodial
tBTC (Threshold)~$200M⚠️ PartialYESYESBridge
BitProof ₿🚀 0→∞NONENEVERNEVERZero
Live on Starknet Sepolia

Real transactions.
Real proof.

Both contracts deployed and verified. Every transaction on-chain, publicly auditable.

Transaction 1 — Credential Issuance
submit_btc_proof()
0x54c6f6c10090a55b1f21e2866729075b8c8c999bb7593317caf07308f00e586
Functionsubmit_btc_proof
Verified Amount1,000,000 sats (0.01 BTC)
Verificationsecp256k1 ✓
Gas Fee$0.0067
StatusAccepted on L2 ✓
View on Voyager ↗
Transaction 2 — Loan Approved
borrow_usdc(500)
0x3999dc7b39b8ea6f7bb9af1232727bff5ee2e039240019548c56d878987737f
Functionborrow_usdc
Amount500 USDC
Oracle Result0x1 = true ✓
Gas Fee$0.00047
StatusAccepted on L2 ✓
View on Voyager ↗
BTCProofOracle Contract
0x07f5fea43431afb8593a12a9fa5776c5b0ecb391307604f3db6e29780bd5d890
MockLender Contract
0x008e23588df852c0bd33994ab69baec1f4a9bcdc2bd01053782ae3c3b06b8787
Tech Stack

Built on real infrastructure.

◆
Cairo 2.x
Smart Contracts
🟧
Starknet
L2 Infrastructure
₿
Xverse
BTC Wallet + API
▲
Next.js 14
Frontend
🔷
Starknet.js
On-chain Calls

The missing primitive
is here.

BitProof is open source and live on Starknet Sepolia right now. Try it. Fork it. Build on it.

GitHub ↗