On August 2nd, 2016 “Tom Elvis Jedusor” posted an .onion link to a text file on IRC, titled MIMBLEWIMBLE and dated July 19. This file illustrated how to construct an electronic cash system with several privacy-enhancing techniques initially envisioned for Bitcoin, such as confidential transactions, non-interactive merging of transactions, and cut-through of transaction inputs and outputs. This talk will be divided in two parts: in the first, we will explore the major ideas behind MimbleWimble; in the second, we will construct and prove the security of a simplified version of MimbleWimble using only simulation-extractable proof systems and homomorphic commitment schemes.