Using Foundry version 1.7.6, I had to remove this line to get the MoneyRouter example tests working: https://github.com/superfluid-finance/super-examples/blob/1384869c67366c5e543012a363bff3bb2e67660a/projects/money-streaming-intro/money-streaming-intro-foundry/test/MoneyRouter.t.sol#L6 Maybe it's just me, logging it here to let you know.