Clipper Decompiler -
Solidity’s move toward the intermediate representation (IR) broke almost every legacy decompiler. Clipper was built post-IR. It understands the optimizations the Solidity compiler makes when using via-ir , meaning it can decompile the most modern, gas-optimized contracts without vomiting errors. Use Case: The $50 Million Heist Consider a recent hypothetical exploit: A flash loan attack on a lending pool. The attacker’s transaction is on-chain forever. The team has the bytecode of the attacking contract, but the source code is private.
The EVM is stack-based and untyped. A uint256 looks exactly the same as an address or a bytes32 to the machine. Clipper employs heuristic taint analysis to guess types. If a value is used in CALL (the opcode for sending ETH), Clipper flags it as an address payable . If a variable is used in EXP , it is likely a power. This recovery turns var1 + var2 into userBalance + withdrawalAmount .
Traditional decompilers have existed for years (notably, Panoramix and the older Remix decompiler). However, they struggle with modern Solidity quirks: the IR-based compilation pipeline (via Yul), optimized bytecode, and the complex control flow of upgradeable proxies. They often produce code that is logically correct but structurally illegible—filled with goto statements and anonymous variables named var0 , var1 , var2 . Clipper was built not just to decompile, but to restore intent . Developed by a team of security researchers who grew tired of reverse-engineering hacks under a ticking clock, Clipper focuses on three core pillars: clipper decompiler
A researcher pastes the bytecode into Clipper. Within seconds, the tool returns a structured output:
Clipper is to EVM reverse-engineering what the microscope was to biology. It doesn't create new dangers; it merely illuminates the ones that have always existed in the dark. For anyone serious about blockchain security, Clipper isn't just a nice-to-have tool—it is the new standard of care. Use Case: The $50 Million Heist Consider a
// Clipper Output (Simplified) function executeFlashLoan(uint256 amount) external { // Recovered logic pool.flashLoan(amount, address(this)); uint256 debt = amount + amount * fee / 10000; // Attacker logic recovered uint256 manipulatedBalance = oracle.manipulate(amount); require(manipulatedBalance > debt, "Not profitable"); pool.repay(debt); emit Steal(manipulatedBalance - debt); }
It is no longer enough to just verify your contract on Etherscan. In the future, auditors will run your bytecode through Clipper to see if the decompiled logic matches your claimed source code. The EVM is stack-based and untyped
However, as an open-source tool gaining traction in major security firms (Trail of Bits, ConsenSys Diligence), Clipper represents a maturation of the Web3 security stack.






