Amazon has made training sessions for SageMaker AI serverless model customization generally available. The feature lets users write and coordinate their own post-training loop—including custom loss functions, reward signals, or multi-turn reinforcement learning—while SageMaker AI manages the underlying infrastructure.

According to AWS, the service handles GPU allocation, distributed execution, fault recovery, and checkpoint storage, removing the need for users to directly manage GPUs.

Why it matters

Managing GPU infrastructure for model customization is a common operational burden. By handling allocation, distributed execution, and fault recovery while leaving the training logic to the user, the offering separates infrastructure concerns from experimentation.

Who should care

Teams performing post-training customization—such as those using custom loss functions, reward signals, or reinforcement learning—may be interested in this generally available option on AWS.