Overview of the child as hacker hypothesis. a: Code can be changed using many techniques (x-axis) and assessed according to many values (y-axis). Standard learning models in machine learning and psychology (green region) tend to focus solely on tuning the parameters of statistical models to improve accuracy. Recent LOT models (red region) expand this scope, writing functions in program-like representations and evaluating them for conciseness and sometimes efficiency. Yet, the set of values and techniques used by actual hackers (and by hypothesis, children; blue region) remains much larger. b: A comparison of three families of developmental metaphors discussed in this paper—the child as scientist, the workshop and evolutionary metaphors, and the child as hacker—along three dimensions: the kinds of knowledge learners acquire, the primary objectives of learning, and the mechanisms used in learning.