Random testing of a higher-order blockchain language (experience report)

We describe our experience of using property-based testing---an approach for automatically generating random inputs to check executable program specifications---in a development higher-order smart contract language that powers state-of-the-art blockchain with thousands active daily users. outline the process integrating QuickChick---a framework testing built on top Coq proof assistant---into real-world implementation in OCaml. discuss challenges we have encountered when well-typed programs realistic language, which mixes purely functional and imperative computations features runtime resource accounting. set properties tested, as well semantic harness required enable their validation. The range from standard type safety soundness control- type-flow analysis used by optimizing compiler. Finally, present list bugs discovered rediscovered help QuickChick severity possible ramifications.