Modern systems need to manage an increasing amount of data. Amazon’s Simple Storage Service (S3) is an important building block for large data applications. In this talk, we will share our experiences and lessons learned from using S3 in Java-based systems. We'll cover technical challenges that Java developers face when writing S3 code with the AWS SDK. We will discuss design decisions, application dependencies, and error handling. We'll share mistakes that we made and bugs that we encountered.