Swap between chains
Your keys, your coins. No custodian.
0.4% protocol fee (min 546 sats) paid as a separate output in the funding transaction — not deducted from funding amount. Please don't send funding directly to the DLC address.
How it works
- Create — Enter amount and sign. Your swap is added and matched automatically.
- Fund — Sign the transaction to lock your funds. Both sides fund; the system tracks it.
- Confirm — Wait for block confirmations (~3 BTC, ~10 FB, ~6 LTC, ~6 BEL).
- Claim — Sign the claim transaction. You receive your funds.
Funds stay on-chain. If the other party disappears, you can refund after the time limit.
Bridge activity
Live stats and recent swaps across the network
Open orders
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Recent completions
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My swaps
Connect a wallet to see your swaps
Unlock your BTC. Earn yield on idle coins.
Non-custodial cross-chain lending. Borrow against collateral. Lend and earn interest.
Borrow against your BTC
Lend and earn interest
Open requests
My Loans
How cross-chain DLC lending works
For Borrowers
- Use your BTC as collateral to get liquidity in LTC, BEL, DGB, or GRS
- Keep your BTC exposure — no selling, no taxable event
- Safety timeout guarantees you can always recover your collateral
For Lenders
- Earn interest on idle coins by funding loan requests
- Over-collateralized: 75% LTV means 133% collateral ratio
- If borrower defaults, you claim BTC at a discount — profitable either way
All funds locked in Taproot Discreet Log Contracts (3-leaf MAST). Oracle can only co-sign lender claims — cannot move funds alone. CLTV safety timeout: borrower can always self-recover.
Common Questions
What do lenders earn?
Interest paid by the borrower (1-20%, set by market). Loans are over-collateralized at 60-85% LTV, so if a borrower defaults, you claim their BTC collateral at a discount. Either way, you profit.
Is my collateral safe?
Collateral is locked in a 3-leaf Taproot DLC on-chain. Nobody can move it without the correct signatures. If everything fails, a safety timeout lets the borrower reclaim after ~90 days.
What if the borrower doesn't repay?
Our oracle attests the default once the loan term expires. The lender claims the BTC collateral — worth more than the loan provided. You signed up for interest but got discounted BTC instead.
What if the BTC price drops?
If the collateral ratio hits 90% LTV, the oracle triggers automatic liquidation. The lender claims collateral before it drops below the loan value. Lenders are protected.
What if the server goes down?
Safety timeout is a pure on-chain timelock (CLTV). After ~90 days, the borrower can always reclaim using just signer.py. No third party needed. No permanent loss.
$1.8 trillion of idle BTC. Earn yield. Borrow without selling.
Bridge between chains
Your keys, your coins. No custodian. P2P atomic swaps — you sign every transaction.
The journey
Questions we hear
Real answers
What even is this?
A swap service for BTC, FB, LTC, BEL, DGB, GRS. You send on one chain, receive on another. You're matched with a real person going the opposite direction — no pools, no wrapped tokens, no one holding your keys.
Is my money safe?
Yes. Funds stay on-chain in locked contracts. NexumBit never touches your keys — you sign every tx. If we disappear, the recovery kit lets you claim or refund yourself. You can always get your money back as long as it's not claimed by the other party.
How long does it take?
Matching depends on platform activity. After matching and users fund, confirmations run ~10–50 min. Then you claim. Total: ~15–95 min depending on chains.
What if they ghost?
Before you fund: Unmatch. After you fund: wait for the timeout, Refund, coins back.
I closed my browser. Now what?
Your funds are locked on-chain. Reconnect, hit My Swaps, your swap's there. Claim or refund when you're ready.
What wallets work?
BTC/FB: UniSat, OKX. LTC: Litescribe. BEL: Nintondo in-browser, or connect external bel1p… and use psbt-signer/signer.py (network bel). DGB / Groestlcoin (GRS): external Taproot + same tool (networks dgb, grs). Derive addresses: python3 signer.py derive-bel, derive-grs, derive-dgb, derive-ltc.
Open source
Build & recover
The NexumBit protocol is fully open. Run the signer when the platform is down, or dive into the spec.
For the curious — DLCs, recovery, terms
Bitcoin stack
NexumBit runs on the Bitcoin stack: Taproot (P2TR), Schnorr signatures, Discreet Log Contracts, and adaptor signatures. Each DLC is a Taproot output with two script paths — a claim path (adaptor + receiver sig) and a refund path (sender sig after timeout). No custom VM, no sidechains for the core swap logic.
How matching works
A background service scans the order book every ~5 seconds. It looks for pairs: same amount class, opposite directions (e.g. BTC→FB vs FB→BTC), rates within slippage. When compatible, it generates shared DLC descriptors and an adaptor secret, pairs the swaps, and both users get funding addresses.
How it's built
Backend handles matching, on-chain monitoring, and transaction building. Rates come from live markets. The web app connects to supported wallets for signing. No custom infrastructure — standard Bitcoin tooling.
How it's used
Create order → get matched → fund your DLC → wait for confirmations (3 BTC, 10 FB, 6 LTC, 6 BEL, 6 DGB, 6 GRS) → claim when ready. Or unmatch before funding; or refund after timeout if things stall.
Possibilities
Both fund and claim — swap completes.
One doesn't fund — unmatch before you fund; after you fund, wait for timeout then refund.
Both fund, counterparty abandons — claim what they locked, refund yours after timeout.
Rate moved beyond slippage — refund when eligible.
Backend down — use the recovery kit to build and sign claim or refund yourself.
Stuck waiting for confirmations — the app tracks it; claim when ready.
No expiry on the claim path — take your time.
What's a DLC?
Discreet Log Contract: an on-chain contract that locks your coins until the swap completes or a timeout hits. No one moves them without your signature. The two sides are cryptographically linked via an adaptor — both claim or both refund.
Adaptor & recovery
When you claim, the adaptor signature is revealed on-chain. The counterparty can extract it and claim their side (that's the atomic link). We embed the adaptor in claim PSBTs so most users just sign and broadcast. Skilled users can use the recovery kit — raw contract data and adaptor secret — to build and sign transactions without us.
Terms
Stay online to sign the claim once confirmed. Can't? Refund after timeout. Blockchain fees apply. Recovery kit always available in swap details.
Ready to swap?
Go to Bridge