LusoCryptoLabs

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Cardano ⇄
CKB Bridge.

Type
Lock-and-mint bridge
Year
2025
Scope
Protocol · dApp · Ops
Chains
Cardano · Nervos CKB
Cardano to CKB Bridge interface

A bidirectional lock-and-mint bridge between Cardano and Nervos CKB, designed so a compromised committee still can't drain the peg.

Bridges get drained through correlated key custody, not clever maths. We built the safe baseline (a 3-of-5 committee with independent signers), then wrapped it in the defences that actually stop a drain: an optimistic challenge window, a permissionless fraud watchtower, caps and self-custody refunds.

On the CKB leg, committee authorisation is post-quantum: signatures are verified in-script with ML-DSA-44, so Shor's algorithm doesn't break the peg. Replay protection scales to O(1) via accumulator roots: a Sparse Merkle Tree on CKB, a Merkle Patricia Forestry on Cardano.

Each signer independently re-verifies the source event: a forged claim never reaches quorum, and one honest watchtower beats a fully colluding committee.
From the threat model

Outcomes

The numbers.

4/4
Transfer directions live on testnet
ML-DSA
Post-quantum committee auth
1-of-N
Watchtower veto on fraud

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