The (Senior) Customer Success Manager role at FactFinder involves managing a portfolio of 40-50 eCommerce clients, focusing on their adoption and growth within the B2B SaaS environment. Key responsibilities include defining client goals, preventing churn, overseeing expansion efforts, and facilitating business reviews. Candidates should have several years of experience with B2B SaaS clients, a strong technical understanding, and the ability to translate customer needs into actionable insights.