200-byte Oraclize callback proxy that forwards oracle results to multiply().
Historical Significance
Concrete on-chain evidence of Oraclize integration patterns in mid-2016, deployed weeks before the DAO fork. Oracle-consuming dApps were already deploying per-request callback proxies at this point: each is a minimal forwarder holding nothing but a target address, discarding the oracle payload and simply poking the consumer contract to re-read state.
Key Facts
Description
A 200-byte Oraclize callback receiver. Its only dispatch entry is __callback(bytes32,string) (selector 0x27dc297e), the method Oraclize calls to deliver an oracle result. The handler forwards control by calling multiply() (selector 0xf3593cd0) on the target contract held in storage slot 0. Runtime bytecode reproduced byte-for-byte with solc 0.3.6, optimizer enabled at 200 runs. Verified on Sourcify and Etherscan.
Source Verified
Homestead Era
The first planned hard fork. Removed the canary contract, adjusted gas costs.
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)
contract Target {
function multiply();
}
contract Callback {
Target target;
function __callback(bytes32 myid, string result) {
target.multiply();
}
}