In June 2016, $50 million dollars was drained from The DAO using a reentrancy attack. This attack actually had the Ethereum foundation rollback the hack and this lead to the fork of Ethereum classic and Ethereum – This makes the testing of smart contracts even more important.
In this video I talk about the new Fuzzing platform from Consensys Diligence. Allowing us to test our code with millions of inputs that would be impossible for us to do alone.