Predictive Horizontal Pod Autoscaler provides executable Predictive Horizontal Pod Autoscaler logic, which can be built into a Custom Pod Autoscaler. The Horizontal Pod Autoscaler has two modes, metric gathering and evaluation. Metric mode gathers metrics, taking in a resource to get the metrics for and outputting these metrics as serialised JSON. Evaluation mode makes decisions on how many replicas a resource should have, taking in metrics and outputting evaluation decisions as seralised JSON. The predictive element uses past evaluations to predict how to scale in the future.