5/5
_Follow along with this video:_ --- ### CODECOPY Before moving forward, there's one specific op code that I wanted to bring to your attention, `CODECOPY`. Represented by the hexadecimal `39`, this op code is a clear indication of where `Contract Creation` occurs in bytecode (though this can also be seen in Runtime). Let's take a look at our Huff contract's output again: ``` 60008060093d393df3 ``` Just as expected, we can see the `39` op code 6 places from the right. This is our flag indicating the creation of our Huff contract on-chain! I absolutely recommend looking at [**evm.codes**](https://www.evm.codes/?fork=shanghai) for an interactive way to learn more about specific op codes in an interactive way.
A deep dive into the CODE COPY opcode for solidity smart contracts. This lesson breaks down what the CODE COPY opcode does, how it’s used in Solidity code, and why it’s a valuable tool for developers working on smart contracts.
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Course Overview
About the course
Assembly
Writing smart contracts using Huff and Yul
Ethereum Virtual Machine OPCodes
Formal verification testing
Smart contract invariant testing
Halmos, Certora, Kontrol
Security researcher
$49,999 - $120,000 (avg. salary)
Smart Contract Auditor
$100,000 - $200,000 (avg. salary)
Guest lecturers:
Josselin Feist
Head of Blockchain at Trail of Bits
Last updated on May 28, 2025
Solidity Developer
Assembly and Formal VerificationDuration: 30min
Duration: 4h 38min
Duration: 3h 57min
Duration: 1h 56min
Course Overview
About the course
Assembly
Writing smart contracts using Huff and Yul
Ethereum Virtual Machine OPCodes
Formal verification testing
Smart contract invariant testing
Halmos, Certora, Kontrol
Security researcher
$49,999 - $120,000 (avg. salary)
Smart Contract Auditor
$100,000 - $200,000 (avg. salary)
Guest lecturers:
Josselin Feist
Head of Blockchain at Trail of Bits
Last updated on May 28, 2025