claude-dev-suite Statechains
A statechain transfers ownership of a UTXO off-chain without moving funds on chain. Each transfer is signed by the current owner
- a Statechain Operator (SO).
Original concept: Ruben Somsen, 2018. Production impl: Mercury Layer by CommerceBlock.
Mechanism
A statechain UTXO is locked in 2-of-2 multisig with:
- The current owner.
- The Statechain Operator.
To transfer:
- Owner A reveals their key share to recipient B.
- SO signs a new transfer message: "this UTXO now belongs to B".
- SO publishes signed proof.
- B confirms receipt; SO can no longer sign for A.
Result: UTXO ownership has moved from A to B without on-chain tx.
Security model
- Trust the SO not to collude with prior owners.
- Worst case: SO + A collude to spend the UTXO, defrauding B.
- Mitigation: SO publishes a "proof of statechain" log; if detected, slashing / reputation loss.
Mercury Layer
CommerceBlock's implementation:
- Open source (MIT).
- SO runs a server, users a client.
- Atomic swaps between statechains supported.
- Liquidity offered for trading without on-chain settlement.
Compared to Spark / Ark
| Aspect | Statechains | Spark | Ark |
|---|---|---|---|
| Operator type | Single (or 1-of-n) | FROST k-of-n threshold | k-of-n cosigners + ASP |
| Key sharing | Per transfer | Aggregate via FROST | VTXO-based |
| On-chain unilateral exit | yes | yes (via leaves) | yes (after CSV) |
| Status | Live (Mercury) | Live beta (Spark) | Live (ARKADE) |
Spark and Ark are statechain-derived but with stronger security (threshold operators, no single point of failure for SO).
Use cases
- Off-chain instant settlement between participants.
- Atomic swaps across statechains (e.g., BTC ↔ LBTC).
- DEX-like UTXO trading.
Limitations
- 1-of-N trust on SO.
- Single SO availability = single point of failure.
- Not as scalable as Lightning for high-frequency micropayments.