Introduction: Designing Libraries and SDKs

A library provides reusable code to another part of a product or another team. An SDK, or software development kit, may also include tools, documentation, sample apps, and UI components.

In this chapter, the caller is usually another engineer. Your design must explain what that engineer can rely on without reading the implementation.

The host app owns the product

The host app includes the library. It owns the user experience, permissions, release schedule, and overall resource budget.

An SDK must not silently take control of these decisions