EuroPython 2022 - ShapePipe: A modular weak-lensing processing and analysis pipeline - presented by Samuel Farrens [Liffey Hall 1 on 2022-07-14] 1. Why would you want to listen to this talk? Cosmology is the study of the origin, evolution, structure and ultimate fate of the Universe. From the largest galaxies down to the smallest Python programmers our story begins with the *Big Bang* . The particles that make up all of things we can touch and see only account for 5% of the energy density of the Universe. Leaving us quite literally in the dark! Weak gravitational lensing, a barely perceptible change to the shape of *galaxies* that we observe, is an indispensable tool for understanding the nature of *dark matter* and *dark energy*. However, measuring the shape of galaxies to the precision required is actually quite a tricky problem. What could be more interesting? 2.What does this have to do with Python? Well, Python has steadily become the standard programming language for cosmologists over the last decade or so... and we are no exception! In this talk I will describe the tools we have developed in Python to help us solve some of the problems with measuring the shapes of galaxies and how various existing Python packages have made this possible. We hope that some of the things we have learned could be useful to other teams, in particular those developing scientific software. 3. Resources - ShapePipe Repository: https://github.com/CosmoStat/shapepipe - ShapePipe Documentation: (https://cosmostat.github.io/shapepipe/ - Slides: https://drive.google.com/file/d/1vQYCV1278oUvFzqGID6yhbQwwDyboCIv/view?usp=sharing This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License http://creativecommons.org/licenses/by-nc-sa/4.0/