Architecture

Purpose

This document describes the developer-facing architecture of a reusable React component library. It focuses on runtime design, module boundaries, and public API behavior, not repository workflows or release process details.

Architectural Principles

• Keep components presentational and domain-neutral.
• Push product behavior to integration layers through props and callbacks.
• Expose stable, typed public APIs.
• Prefer composition over inheritance.
• Keep modules side-effect free by default for better tree-shaking.

Layered Model

Runtime Boundaries

Public Surface

• The package entrypoint exports intentionally supported components, types, and utilities.
• Consumers interact only with documented exports and props.

Component Modules

• Each component owns its rendering logic, public prop types, and interaction behavior.
• Components should not import host application state, routing, auth, or business services.

Primitive Composition Layer

• Components are built from accessible, low-level UI primitives.
• Primitive wrappers remain implementation details unless explicitly exported.

Utility Layer

• Shared helpers stay pure and framework-agnostic where possible.
• Utilities should support component behavior without becoming domain service layers.

Style And Token Layer

• Styles rely on semantic tokens and predictable class composition.
• Token names should be namespaced to reduce collisions in host applications.
• Theme changes should be possible without changing component APIs.

API Design

• Use explicit TypeScript props for all public components.
• Favor additive, composable props over tightly coupled configuration objects.
• Model access and policy behavior through injectable contracts (for example, required capabilities plus resolver callbacks).
• Keep uncontrolled and controlled usage patterns clear when both are supported.

Contract-Driven Development Model

• Define component behavior in machine-readable contracts.
• Keep implementation, tests, and docs aligned with contract states.
• Treat contracts as executable architecture rules for behavior, accessibility, and interaction guarantees.

Accessibility

• Interactive components must provide keyboard support and visible focus behavior.
• Inputs and form controls must preserve correct labeling and aria state.
• Overlay and popover-like interactions must provide predictable focus management and dismissal behavior.