Trees is an open-source file tree rendering library published as @pierre/trees, designed to help developers build high-performance, interactive file explorer interfaces for web applications. It focuses on flexibility, accessibility, and scalability, enabling developers to render and manage large hierarchical datasets such as file systems with minimal performance overhead.

The library provides a fully customizable tree component that supports advanced UI behaviors like drag-and-drop, context menus, search filtering, and Git status indicators. Developers can tailor both behavior and appearance through configuration options, custom renderers, and CSS variables, making it adaptable to a wide range of developer tools and applications.

A key feature of Trees is its built-in virtualization system, which ensures efficient rendering even for very large datasets containing thousands of nodes. Only visible elements are mounted in the DOM, allowing near-instant rendering and smooth interaction regardless of tree size.

Trees also emphasizes accessibility, implementing keyboard navigation, ARIA roles, and compliance with WCAG guidelines out of the box. This ensures that tree interfaces built with the library are usable by a wide range of users without requiring additional accessibility work.

The library includes features such as flattening nested directories, visual indicators for version control changes, and multiple search modes for filtering hierarchical data. It also supports theming through Shiki-compatible styles and configurable icon sets, enabling consistent integration with developer environments and design systems.

Trees is built for modern JavaScript ecosystems and can be integrated into frameworks like React or used with vanilla JavaScript. It is positioned as a developer-focused UI component library for building file explorers, code editors, and other hierarchical data interfaces.

Key features include:

• High-performance rendering with built-in virtualization for large trees
• Fully customizable UI with CSS variables and render hooks
• Drag-and-drop support for file and folder manipulation
• Search and filtering with multiple display modes
• Git status indicators for file changes
• Context menu composition for file operations
• Keyboard navigation and ARIA-based accessibility support
• Configurable icon sets and theming support

Common use cases include:

• Building file explorers in IDEs or web-based editors
• Creating hierarchical navigation systems
• Visualizing structured datasets or directories
• Developing developer tools and dashboards
• Implementing Git-aware file trees

Trees is developed by The Pierre Computer Company and released as an open-source library focused on delivering performant and accessible tree-based interfaces for modern web applications.