echidna by hairyf/blockchain-master

Skill is based on Echidna (crytic/echidna), generated from source at the listed date.

Echidna is a property-based fuzzer for Ethereum smart contracts. It generates random sequences of contract calls to falsify invariants (Solidity functions named with a prefix like echidna_ that return bool) or to trigger Solidity assert failures. It supports coverage-guided fuzzing, corpus collection, multiple test modes, and integration with Foundry, Hardhat, and Truffle.

Core References

Topic	Description	Reference
Invariants	Defining and running property invariants (echidna_ prefix, no args, return bool)	core-invariants
Configuration	YAML config (testMode, gas, coverage, corpus, workers, filtering)	core-configuration
CLI	Invocation, contract selection, output drivers (text, json, none)	core-cli

Features

Topic	Description	Reference
Coverage and corpus	corpusDir, covered.txt, line markers, coverage reports	features-coverage
Build systems	Foundry, Hardhat, Truffle, echidna ., allContracts, solcLibs	features-build-systems
Test modes	property, assertion, overflow, exploration, optimization	features-test-modes
Function filtering	filterFunctions, filterBlacklist, whitelist/blacklist	features-filtering
Symbolic execution	symExec, SMT solver (cvc5, z3, bitwuzla), tuning options	features-symbolic
FFI and cheatcodes	allowFFI, HEVM cheatcode support	features-ffi-cheatcodes

Best practices

Topic	Description	Reference
Invariant patterns	Multi-sender, payable, gas/time, assertions vs invariants	best-practices-invariants

Advanced

Topic	Description	Reference
JSON output	Campaign/Test/Transaction schema for CI and scripting	advanced-json-output
Debugging	Profiling (+RTS -p -s), common performance causes	advanced-debugging