echidna

Fuzz test Ethereum smart contracts for property violations via stateful transactions.

Updated Aug 27, 2026
One-click install
npx skills add https://github.com/0xinit/cryptoskills --skill echidna-0xinit
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: echidna
Source: https://github.com/0xinit/cryptoskills/tree/main/skills/echidna
Command: npx skills add https://github.com/0xinit/cryptoskills --skill echidna-0xinit

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill helps developers find critical bugs in smart contracts that traditional testing methods might miss, by using stateful fuzzing to uncover vulnerabilities.

Core Features & Use Cases

  • Property-Based Fuzzing: Define invariants your contract must uphold and let Echidna find violations.
  • Stateful Testing: Echidna generates sequences of transactions, mimicking real-world interactions.
  • Use Case: A DeFi protocol developer uses Echidna to fuzz their lending contract, defining properties like "total collateral value must always exceed total debt." Echidna discovers a sequence of operations that leads to insolvency, preventing a potential exploit.

Quick Start

Use the echidna skill to fuzz the contract located at 'test/MyTest.sol'.

Frequently Asked Questions about echidna

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I find smart contract bugs that traditional testing misses?▼

Stateful property-based fuzzing finds smart contract bugs by generating sequences of transactions to uncover vulnerabilities. You define invariants your contract must uphold, and the fuzzer identifies state transitions that violate these properties.

What is property-based fuzzing for Ethereum smart contracts?▼

Property-based fuzzing for Ethereum smart contracts is a testing technique where you define invariants your contract must uphold. The fuzzer then generates stateful transaction sequences to discover violations of these defined properties.

How do I run stateful fuzz tests on a Solidity contract?▼

To run stateful fuzz tests on a Solidity contract, compile your code and execute it within an EVM environment. Point the fuzzer at your test contract file, such as 'test/MyTest.sol', to begin generating transaction sequences.

Can I use this fuzzer to test DeFi lending protocol invariants?▼

Yes, you can use this fuzzer to test DeFi lending protocol invariants. By defining properties like total collateral value must always exceed total debt, the fuzzer generates transaction sequences to identify operations leading to insolvency.

Does property-based fuzzing require a specific EVM environment setup?▼

Yes, property-based fuzzing requires Solidity compilation and execution within an EVM environment. This setup allows the fuzzer to accurately analyze contract state transitions and generate valid stateful transaction sequences.

What is the difference between stateful fuzzing and traditional smart contract testing?▼

Unlike traditional testing, stateful fuzzing generates sequences of transactions mimicking real-world interactions. This approach uncovers critical vulnerabilities by analyzing complex state transitions rather than just isolated function calls.