# Cross-chain Receipts

Portable proofs that travel with assets. Independent verification across chains without trusting bridges.

## Cross-chain Expands Attack Surfaces

Composability within one chain is not the same as interoperability across chains. Current approaches inherit the weakest link's vulnerabilities.

### Bridge Exploits

Billions lost to bridge hacks. Message-passing creates single points of failure that attackers exploit.

### Unverified Inputs

Transactions assume validity without independent verification. Errors propagate before detection.

### MEV Extraction

Fast execution hides downstream costs. Front-running and MEV make high-value cross-chain transfers risky.

## Layer 0 as Neutral Rails

Geeq provides independent, portable verification that any L1/L2 can anchor to. No shared failure modes. No bridge trust assumptions.

### Portable Proofs

Cryptographic receipts travel with assets across any chain or environment.

### Independent Verification

Each chain verifies independently. No trust assumptions about other validators.

### Contained Failures

Issues on one chain don't cascade. Fault containment by design.

### MEV-Free Settlement

No front-running or value extraction during cross-chain transfers.

## How Cross-chain Receipts Work

1. **Transaction on Chain A**  
   Asset or data recorded with cryptographic proof on the originating chain.

2. **Receipt Generated**  
   Geeq issues a portable receipt proving the transaction's validity and timing.

3. **Proof Travels**  
   Receipt accompanies the asset to Chain B. No bridge or oracle required.

4. **Independent Verification**  
   Chain B verifies the receipt independently before accepting the asset.

## Verification Over Trust

Compare Geeq's Layer 0 approach against current cross-chain solutions

| Feature                         | Geeq L0                       | Bridge Messaging              | Shared Security                |
|---------------------------------|-------------------------------|-------------------------------|-------------------------------|
| Trust Model                     | Independent verification       | Bridge operators              | Validator overlap              |
| Failure Mode                    | Contained                     | Cascading                    | Cascading                     |
| Proof Portability               | Native                        | Message-dependent             | Chain-dependent                |
| MEV Exposure                    | None                          | High                          | Inherited                     |
| Single Point of Failure         | None                          | Bridge contracts              | Shared validators              |

## Design Principles

### Verification Before Execution

Don't assume shared security or consensus. Verify independently first, then proceed.

### Proofs Travel With Assets

Interoperability shouldn't inherit the weakest link. Portable proofs maintain integrity.

### No Single Points of Failure

Eliminate bridges, oracles, and shared validators as attack vectors.

### Checkpoints Over Speed

Boring infrastructure (proofs and receipts) offers more security than fast execution.

### Explicit Consent

Transactions represent valid intent. No unauthorized token pushes or unverified events.

### Immutable Ledgers

Cryptographic rails prevent history rewriting. Full accountability for all actions.

## Build Cross-chain Security

Integrate Geeq's portable receipts into your multi-chain architecture.