State on the Chain

Testing & deploying with Foundry

Lesson 4 of 5

Foundry tests are Solidity too. Write unit tests, let the fuzzer hunt for inputs that break your invariants, run a local chain, then deploy to a testnet and verify the source.

What you'll learn

Write a Foundry test that impersonates callers and expects specific reverts
Explain fuzz testing and state the invariant a fuzzer should never be able to break
Run the deploy loop: anvil locally, then Base Sepolia with source verification

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