SmartPy is a complete system to develop smart-contracts for the Tezos blockchain. It is an embedded EDSL in python to write contracts and their tests scenarios. It includes an online IDE, a chain explorer, and a command line interface. Python is used to generate programs in an inperative, type infered, intermediate language called SmartML. SmartML is also the name of the OCaml library which provides an interpreter, a compiler to Michelson (the smart-contract language of Tezos), as well as a scenario “on-chain” interpreter. The IDE uses a mix of OCaml built with js_of_ocaml and pure Javascript. The command line interface also builds with js_of_ocaml to run on Node.js.