A BlackRock Aladdin developer works on the Aladdin platform, a comprehensive investment management system used by BlackRock and its clients. Their duties include building and maintaining software applications, debugging and resolving software bugs, and improving system performance. They also work on developing new features and functionalities for the system, ensuring the security of the platform, and integrating other systems with the Aladdin platform. These developers also collaborate with other stakeholders to understand their needs, translate them into technical requirements, and ensure the delivery of high-quality solutions. They need to have strong programming skills and a deep understanding of financial markets.