"Echidna" is a fuzzing / property-based testing tool for Ethereum Smart Contracts. With Echidna you can generate random input data according to your Smart Contract ABIs.
This is very useful for automated tests as you don't have to come up with the assertions but Enchida does. Once a problem is found, Echidna lets you further shrink down the input domain to find an exact way to reproduce the issue.
Protip: Use Etheno to simplify the setup of Echidna in large multi-contract projects.
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