Nearly every day, we interact with recommendation systems on social media, e-commerce, and other services and applications. These recommendation systems can influence what we read, what we buy, and even how we think. To better understand the impact of recommendation systems and other sociotechnical systems (for example, on political polarization and misinformation diffusion), Eli Lucherini has OSS’ed T-RECS, a Python package to simulate how an algorithm mediates interactions between different stakeholders. T-RECS offers a simple, modular programming interface, which enables users to focus on the scientific assumptions behind their simulations instead of on the mechanics of the simulator. It also includes a pre-populated library of common recommender systems models and system elements.