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Over 150 interview questions for Ethereum Developers All of these questions can be answered in three sentences or less. Easy What is the difference between private, internal, public, and external...
Last updated on Oct 29, 2025
AliasCheck and Num2Bits_strict in Circomlib An alias bug in Circom (or any ZK circuit language) occurs when a binary array of signals encodes a number larger than the field element can hold. We will...
Last updated on Sep 29, 2025
The initializable smart contract design pattern Initializers are how upgradeable contracts achieve the behavior of a constructor. When deploying contracts, it's common to call a constructor to...
Last updated on Oct 22, 2025
11 min read
ERC-7201 Storage Namespaces Explained ERC-7201 (formerly EIP-7201) is a standard for grouping storage variables together by a common identifier called a namespace, and also to document the group of...
Last updated on Oct 22, 2025
Fixed Point Arithmetic in Solidity (Using Solady, Solmate, and ABDK as Examples) A fixed-point number is an integer that stores only the numerator of a fraction — while the denominator is implied....
Last updated on Dec 5, 2025
The Transparent Upgradeable Proxy Pattern Explained in Detail The Transparent Upgradeable Proxy is a design pattern for upgrading a proxy while eliminating the possibility of a function selector...
Last updated on Oct 29, 2025
Understanding ABI encoding for function calls ABI encoding is the data format used for making function calls to smart contracts. It is also how smart contracts encode data when making calls to other...
Last updated on Aug 29, 2025
Delegatecall: The Detailed and Animated Guide This article explains how delegatecall works in detail. The Ethereum Virtual Machine (EVM) offers four opcodes for making calls between contracts: * and...
Last updated on Oct 20, 2025
2 min read
noDelegateCall Explained The modifier prevents delegatecall from being sent to a contract. We will first show the mechanism for how to accomplish this then later discuss the motivation for why one...
Last updated on Oct 22, 2025
Hacking Underconstrained Circom Circuits With Fake Proofs The operator in Circom can be dangerous because it assigns values to signals but does not constrain them. But how do you actually ~~exploit~~...
Last updated on Aug 10, 2024
The RareSkills Book of Solidity Gas Optimization: 80+ Tips !solidity gas optimization TABLE OF CONTENTS The RareSkills Book of Gas Optimization Gas optimization tricks do not always work Beware of...
Last updated on Oct 22, 2025
46 min read
Smart Contract Security !smart contract security This article serves as a mini course on smart contract security and provides an extensive list of the issues and vulnerabilities that tend to recur in...
Last updated on Oct 29, 2025