Holger Krekel is active in the Python community since 2002. He has given numerous talks including a keynote at EP2015 on the "decentralized web", many trainings on automated testing and packaging. He is a co-founder of the PyPy project and maintains many well-known tools such as tox, pytest and devpi in the Python tooling landscape. His recent technical interests include the building of decentralized and crypto systems and he is increasingly involved in language-unspecific communities.