Design Patterns MCP Server

{ "category": "Cross-Chain", "description": "Cross-Chain design patterns for blockchain and Web3 applications", "patterns": [ { "id": "atomic-swap", "name": "Atomic Swap (HTLC)", "category": "Cross-Chain", "description": "Hash Time-Locked Contracts for trustless cross-chain swaps. Both sides lock with same hash.", "when_to_use": [ "Trustless exchanges", "cross-chain swaps", "P2P trading" ], "benefits": [ "Trustless", "no intermediary", "atomic execution" ], "drawbacks": [ "Requires both chains online", "timelock delays", "UX complexity" ], "use_cases": [ "Bitcoin-Ethereum swaps", "decentralized exchanges" ], "complexity": "Medium", "tags": [ "cross-chain", "atomic-swap", "htlc", "trustless" ], "examples": { "solidity": { "language": "solidity", "code": "// Hash Time-Locked Contract\nfunction lock(bytes32 hashlock, uint256 timelock) external payable {\n require(msg.value > 0);\n swaps[hashlock] = Swap({\n amount: msg.value,\n timelock: block.timestamp + timelock,\n sender: msg.sender\n });\n}\n\nfunction claim(bytes32 preimage) external {\n require(keccak256(abi.encodePacked(preimage)) == hashlock);\n payable(msg.sender).transfer(swaps[hashlock].amount);\n}" } } }, { "id": "burn-mint-bridge", "name": "Burn-and-Mint Bridge", "category": "Cross-Chain", "description": "Burn tokens on source, mint on destination. For native multi-chain tokens.", "when_to_use": [ "Native multi-chain tokens", "no canonical chain", "symmetric chains" ], "benefits": [ "No custodial risk", "symmetric design", "scalable to N chains" ], "drawbacks": [ "Requires token contract control on all chains", "irreversible burns" ], "use_cases": [ "Circle USDC", "native multi-chain protocols" ], "complexity": "Medium", "tags": [ "cross-chain", "bridge", "burn-mint", "multi-chain" ], "examples": { "solidity": { "language": "solidity", "code": "// Source chain: burn\nfunction bridgeBurn(uint256 amount, uint256 destChainId) external {\n _burn(msg.sender, amount);\n emit BridgeBurn(msg.sender, amount, destChainId);\n}\n\n// Destination chain: mint\nfunction bridgeMint(address to, uint256 amount, bytes calldata proof) external onlyRelayer {\n require(verifyBurnProof(proof));\n _mint(to, amount);\n}" } } }, { "id": "ccip-messaging", "name": "CCIP Cross-Chain Messaging", "category": "Cross-Chain", "description": "Chainlink CCIP for arbitrary cross-chain message passing and token transfers.", "when_to_use": [ "Multi-chain dApps", "cross-chain function calls", "oracle-backed bridges" ], "benefits": [ "Oracle security", "programmable tokens", "arbitrary messages" ], "drawbacks": [ "Centralization (oracles)", "fees", "limited chain support" ], "use_cases": [ "Cross-chain lending", "multi-chain NFTs", "composable protocols" ], "complexity": "Medium", "tags": [ "cross-chain", "ccip", "chainlink", "messaging", "oracles" ], "examples": { "solidity": { "language": "solidity", "code": "// CCIP sender\nimport {IRouterClient} from \"@chainlink/contracts-ccip/src/v0.8/ccip/interfaces/IRouterClient.sol\";\n\nfunction sendMessage(uint64 destChainSelector, address receiver, string memory message) external {\n Client.EVM2AnyMessage memory evm2AnyMessage = Client.EVM2AnyMessage({\n receiver: abi.encode(receiver),\n data: abi.encode(message),\n tokenAmounts: new Client.EVMTokenAmount[](0),\n feeToken: address(linkToken),\n extraArgs: \"\"\n });\n \n router.ccipSend(destChainSelector, evm2AnyMessage);\n}" } } }, { "id": "layerzero-omnichain", "name": "LayerZero Omnichain", "category": "Cross-Chain", "description": "Ultra-light node protocol for omnichain applications. Uses oracles + relayers for verification.", "when_to_use": [ "Native omnichain tokens", "cross-chain dApps", "unified liquidity" ], "benefits": [ "True omnichain apps", "low latency", "flexible security" ], "drawbacks": [ "Oracle + relayer trust", "fees", "potential congestion" ], "use_cases": [ "Stargate Finance", "omnichain NFTs", "unified DEXs" ], "complexity": "Medium", "tags": [ "cross-chain", "layerzero", "omnichain", "oracles", "relayers" ], "examples": { "solidity": { "language": "solidity", "code": "// LayerZero omnichain contract\nimport \"@layerzerolabs/solidity-examples/contracts/lzApp/NonblockingLzApp.sol\";\n\ncontract OmniCounter is NonblockingLzApp {\n function incrementCounter(uint16 _dstChainId) external payable {\n _lzSend(_dstChainId, abi.encode(INCREMENT_TYPE), payable(msg.sender), address(0), bytes(\"\"), msg.value);\n }\n \n function _nonblockingLzReceive(uint16, bytes memory, uint64, bytes memory _payload) internal override {\n counter++;\n }\n}" } } }, { "id": "light-client-bridge", "name": "Light Client Bridge", "category": "Cross-Chain", "description": "Verify source chain state using light client proofs. Most trustless but complex.", "when_to_use": [ "Maximum security", "trustless bridges", "consensus proof verification" ], "benefits": [ "Trustless", "cryptographically secure", "no relayer trust" ], "drawbacks": [ "Very high gas costs", "complex implementation", "client maintenance" ], "use_cases": [ "Rainbow Bridge (NEAR-Ethereum)", "IBC (Cosmos)" ], "complexity": "Very High", "tags": [ "cross-chain", "light-client", "trustless", "consensus-proof" ], "examples": { "solidity": { "language": "solidity", "code": "// Verify using light client\nfunction submitBlockHeader(bytes memory header, bytes memory proof) external {\n require(verifyConsensusProof(header, proof));\n blockHashes[blockNum] = keccak256(header);\n}\n\nfunction verifyTransaction(bytes memory txProof, uint256 blockNum) external view returns (bool) {\n return MerkleProof.verify(txProof, blockHashes[blockNum], txHash);\n}" } } }, { "id": "lock-mint-bridge", "name": "Lock-and-Mint Bridge", "category": "Cross-Chain", "description": "Lock assets on source chain, mint wrapped version on destination. Burn to unlock.", "when_to_use": [ "Cross-chain token transfers", "wrapped assets", "multi-chain protocols" ], "benefits": [ "Simple model", "preserves total supply", "reversible" ], "drawbacks": [ "Custodial risk on lock contract", "bridge security critical" ], "use_cases": [ "WBTC", "Polygon bridge", "Multichain (Anyswap)" ], "complexity": "Medium", "tags": [ "cross-chain", "bridge", "wrapped-tokens", "lock-mint" ], "examples": { "solidity": { "language": "solidity", "code": "// Source chain: lock tokens\nfunction lock(uint256 amount) external {\n token.transferFrom(msg.sender, address(this), amount);\n emit Locked(msg.sender, amount, destChainId);\n}\n\n// Destination chain: mint wrapped tokens\nfunction mint(address to, uint256 amount, bytes calldata proof) external onlyRelayer {\n require(verifyProof(proof));\n wrappedToken.mint(to, amount);\n}" } } }, { "id": "optimistic-bridge", "name": "Optimistic Bridge", "category": "Cross-Chain", "description": "Assume relayer messages valid, allow fraud proof challenges. Gas-efficient but delayed finality.", "when_to_use": [ "Cost-sensitive bridges", "high-value transfers", "acceptable latency" ], "benefits": [ "Low gas costs", "simple relayers", "scales well" ], "drawbacks": [ "7-day challenge period", "fraud proof complexity", "liveness assumptions" ], "use_cases": [ "Optimism/Arbitrum native bridges", "Nomad (legacy)" ], "complexity": "High", "tags": [ "cross-chain", "optimistic", "fraud-proof", "challenge-period" ], "examples": { "solidity": { "language": "solidity", "code": "// Optimistic relayer with challenge period\nfunction relayMessage(bytes memory message, bytes memory signature) external {\n require(verifySignature(message, signature));\n messages[messageId] = PendingMessage({\n data: message,\n timestamp: block.timestamp,\n executed: false\n });\n}\n\nfunction executeAfterDelay(bytes32 messageId) external {\n require(block.timestamp >= messages[messageId].timestamp + CHALLENGE_PERIOD);\n _execute(messages[messageId].data);\n}" } } }, { "id": "wormhole-messaging", "name": "Wormhole Cross-Chain", "category": "Cross-Chain", "description": "Guardian network for cross-chain messaging and token transfers. 19 validators sign messages.", "when_to_use": [ "Multi-chain protocols", "cross-chain NFTs", "Portal token bridge" ], "benefits": [ "Wide chain support", "fast finality", "unified SDK" ], "drawbacks": [ "Guardian trust (19 validators)", "hack history", "centralization" ], "use_cases": [ "Portal Bridge", "cross-chain lending", "multi-chain governance" ], "complexity": "Medium", "tags": [ "cross-chain", "wormhole", "guardians", "messaging", "bridge" ], "examples": { "solidity": { "language": "solidity", "code": "// Wormhole message sender\nfunction sendMessage(bytes memory payload) external payable {\n uint64 sequence = wormhole.publishMessage{value: msg.value}(\n 0, // nonce\n payload,\n consistencyLevel\n );\n emit MessageSent(sequence, payload);\n}\n\n// Receiver verifies VAA (Verified Action Approval)\nfunction receiveMessage(bytes memory vaa) external {\n (IWormhole.VM memory vm, bool valid, string memory reason) = wormhole.parseAndVerifyVM(vaa);\n require(valid, reason);\n _processMessage(vm.payload);\n}" } } } ] }