Minimal delegatecall forwarder with a hardcoded implementation address.
Historical Significance
Predates the ERC-1167 minimal-proxy standard and shows the same idea being reinvented independently: put the logic in one implementation contract and give every user a throwaway forwarder.
Key Facts
Description
A compact proxy whose payable fallback copies the incoming calldata into memory and delegatecalls a fixed implementation address returned by an internal constant function, forwarding 63/64ths of the remaining gas and returning a single 32-byte word. The source uses old-style inline assembly labels, so the compiler emits the fallback as a called function. A failed delegatecall jumps to an invalid opcode. The runtime code matches the deployed bytecode byte for byte; only the trailing swarm metadata hash differs, because the EthereumHistory attribution comment changes the source text. Sourcify records this as a partial match and Etherscan shows it as verified.
Source Verified
Bytecode Overview
Verified Source Available
Source verified through compiler archaeology and exact bytecode matching.
View Verification ProofShow source code (Solidity)
// Submitted by EthereumHistory (ethereumhistory.com)
pragma solidity ^0.4.11;
contract Proxy {
function implementation() internal constant returns (address) {
return 0x072461a5e18f444b1cf2e8dde6dfb1af39197316;
}
function () payable {
address target = implementation();
assembly {
let ptr := msize()
mstore(0x40, add(ptr, calldatasize))
calldatacopy(ptr, 0, calldatasize)
jumpi(fail, iszero(delegatecall(div(mul(gas, 0x3f), 0x40), target, ptr, calldatasize, 0, 0x20)))
return(0, 0x20)
fail:
invalid
}
}
}