Gradual Typing
Gradual typing is a type system approach that allows developers to mix statically typed and dynamically typed code within the same program, enabling incremental adoption of type annotations. It provides the flexibility of dynamic typing for rapid prototyping while offering the safety and performance benefits of static typing for critical parts of the codebase. This hybrid model is commonly implemented in languages like Python (with type hints), JavaScript (via TypeScript or Flow), and Racket.
Developers should learn gradual typing when working on large, evolving codebases where full static typing might be too restrictive or costly to adopt all at once. It is particularly useful in projects transitioning from dynamic to static typing, as it allows teams to add type annotations incrementally to improve code reliability, catch errors early, and enhance tooling support like autocompletion. Use cases include maintaining legacy systems, integrating with existing dynamic libraries, or in agile environments where flexibility is prioritized.