Layout composition engines

Atomic Layout is a declarative framework for building responsive user interfaces in React. It functions as a layout engine that abstracts complex grid structures into reusable components, allowing for the creation of hierarchical spatial distributions without the need for manual media queries. The library distinguishes itself by mapping visual layout regions to component structures through dynamic grid-template-area generation. It utilizes a property-based system where components accept specific suffixes to automatically trigger responsive style adjustments based on viewport width. By employi

Rebass is a React design system library that provides a collection of theme-driven, responsive UI primitives. It functions as a theme-based layout engine, using a set of stateless components to standardize spacing, typography, and colors across a user interface. The library distinguishes itself by mapping style properties to a central design theme through a styled-system approach. This allows for responsive style mapping where components automatically adapt their appearance based on screen size and provides the ability to swap underlying HTML elements while preserving styling logic to maintai

This project is a Go WebAssembly frontend framework designed for building interactive web applications. It provides a toolkit for executing Go code directly in the browser to handle client-side logic and user interface development. The framework functions as a declarative UI library and a progressive web app toolset. It enables the creation of installable applications that can operate in standalone windows and maintain offline functionality. The system manages browser-side application development through a component-based view hierarchy and a declarative syntax for defining UI elements. It i

Yoga is an embeddable UI layout library and engine that implements the flexible box model used in web standards. It functions as a cross-platform tool for computing user interface geometry, calculating element sizes and positions without relying on a specific operating system's rendering. The engine provides a portable C++ core to ensure identical layout calculations across Android, iOS, and the web. It utilizes an abstract node interface to separate the layout logic from the host UI framework, allowing it to be integrated into native applications. The system manages interface rendering thro

This is a layout library for Android applications that implements the CSS Flexible Box layout model. It provides a view container and engine that arrange child views by distributing space and aligning content according to a flexible box model. The framework enables the creation of responsive user interfaces that automatically adjust element positioning, wrapping, and growth based on available screen dimensions and orientations. The system includes capabilities for adaptive layout workflows, dynamic element alignment, and a virtualized rendering system for recycling views to display large dat

This project is a multi-platform UI framework designed for building applications that target mobile, web, and desktop environments from a single codebase. It utilizes a declarative paradigm where the user interface is defined as a function of application state, supported by a layered architecture that includes a high-performance rendering engine and a multi-platform compilation model. The framework provides a comprehensive suite of developer tools, including hot reloading for real-time code injection and diagnostic utilities for monitoring application state and performance. It features a modu

Foundation Sites is a responsive front-end framework providing a collection of CSS and JavaScript tools to build websites that automatically adapt to different screen sizes and devices. It functions as a responsive design library and cross-browser UI toolkit, offering a grid layout system and pre-styled interface components to ensure consistent rendering across modern web browsers. The framework enables rapid front-end UI prototyping and the integration of interactive components through a scripting interface that manages the lifecycle of UI plugins. It supports custom CSS framework management

Yoga is a cross-platform layout engine and embeddable core that determines the dimensions and offsets of hierarchical element trees. It provides a C++ implementation of the Flexbox layout model to calculate element positions and sizes based on web standards, ensuring a uniform appearance across diverse devices and operating systems. The engine is designed for portability via a C API, allowing the layout logic to be integrated into various host languages and platforms. It utilizes an incremental layout system that identifies modified subtrees and recalculates positions only for changed nodes a

Flexboxgrid is a responsive CSS framework and layout engine based on CSS3 standards. It provides a grid system that uses the flexbox model to arrange page elements into flexible, proportional grids that adapt to different screen sizes and device resolutions. The framework implements a float-free responsive design, utilizing a media-query breakpoint system to adjust layouts and column counts based on viewport width. It employs percentage-based column sizing and negative-margin guttering to maintain consistent spacing and fluid scaling across various displays. The system maps layout configurat

This project is a responsive layout framework for Angular that provides a system of directives to create adaptive user interfaces using CSS Flexbox and CSS Grid. It includes specialized libraries for managing flexible box alignment and structuring complex two-dimensional page grids. The framework features a breakpoint monitoring service to programmatically observe media query changes and trigger logic when viewport dimensions cross defined boundaries. To optimize performance, it includes a build-time CSS generator that uses SASS mixins to create static media query stylesheets, reducing the ne

Masonry is a declarative UI layout engine and domain-specific language for defining layout constraints on iOS and macOS. It serves as a wrapper for native Apple layout constraints, providing a system for positioning views on a screen by declaring rules and priorities. The library implements a fluent interface that uses chainable method calls to define complex screen layouts. This approach replaces native configuration calls with an expressive syntax for generating layout rules. The engine includes capabilities for managing constraint priorities to resolve layout conflicts and tools for updat

Tamagui is a cross-platform user interface framework designed to build high-performance, themeable applications that share logic and styling across web and mobile environments. It functions as a comprehensive design system orchestrator, providing a collection of type-safe components that compile to optimized atomic CSS for the web and native code for mobile platforms. By utilizing a build-time compiler, the framework eliminates runtime overhead, ensuring consistent visual output and interaction behavior regardless of the target platform. The framework distinguishes itself through its advanced

This project is a cross-platform user interface framework that maps mobile-native component primitives to standard web elements. It enables developers to build consistent applications that function across both mobile and web environments by providing a unified library of components and shared logic. The framework distinguishes itself through a specialized style engine that converts JavaScript object-based declarations into optimized, scoped CSS at runtime. It also features a responsive layout engine that implements a flexbox-based system, ensuring that interfaces adapt dynamically to differen

Rich is a comprehensive library for building sophisticated command-line interfaces and terminal applications. It provides a robust console formatting engine and a layout framework that enables developers to render rich text, syntax-highlighted code, and complex data structures directly in the terminal. By utilizing a recursive constraint-based layout engine, the library allows for the creation of hierarchical grids, panels, and trees that maintain their structure even as terminal dimensions change. What distinguishes the library is its ability to manage persistent, real-time terminal interfac

ComponentKit is a declarative UI framework for building iOS interfaces through composition of small, reusable components. It provides a structured approach to constructing user interfaces where each component is defined as an immutable, pure function of its inputs, enabling predictable rendering and state management. The framework supports both stateless and stateful components, with controllers that can be attached to manage persistent state across component updates. The framework distinguishes itself through its component architecture that emphasizes explicit data flow and compile-time safe

Opentui is a terminal user interface framework for building interactive command line applications. It provides a component-based system featuring a flexbox layout engine, a virtual node component tree, and a low-level 2D cell array renderer. The project is distinguished by a sophisticated keyboard binding engine that maps complex multi-stroke sequences and chords to named commands using prioritized, reactive layers. It also implements a plugin architecture that allows external modules to inject custom UI components into designated layout slots and extend input logic at runtime. Its capabilit

Druid is a native user interface toolkit and 2D graphics engine for the Rust programming language. It functions as a retained-mode, data-driven framework for building graphical user interfaces that run across Linux, macOS, and web browsers via WebAssembly. The toolkit distinguishes itself through a data-first approach to UI design, utilizing lenses to isolate subsets of global application state and synchronize them with specific widgets. This allows the visual layout to update automatically when the underlying data model changes. Its capability surface includes a constraint-based box layout

HeroUI is a declarative toolkit for building accessible user interfaces through modular, React-based component composition. It provides a comprehensive set of reusable building blocks designed to standardize visual language and interaction patterns across web and mobile applications. The library distinguishes itself through an integrated approach to accessibility and styling. It automatically manages state and keyboard interactions by injecting appropriate attributes, while utilizing a utility-driven styling architecture to enforce design system consistency. Developers can leverage polymorphi

AsyncDisplayKit is an asynchronous UI framework and performance library for iOS. It provides a collection of performant alternatives to standard views, allowing developers to build responsive interfaces by offloading layout and rendering tasks to background threads. The framework is centered around a declarative layout engine based on a flexbox model, which calculates element positions and sizes asynchronously. It utilizes a node-based abstraction to wrap native views, enabling the instantiation and configuration of UI hierarchies on background threads to prevent main thread blocking. The sy

React Grid Layout is a toolkit for building draggable, resizable, and responsive dashboard interfaces. It functions as a coordinate-based grid system that reconciles component positions and dimensions through declarative metadata, allowing developers to manage complex collections of UI elements that users can interact with directly. The library distinguishes itself through an automated packing algorithm that maintains structural integrity by shifting elements to fill gaps and resolving overlaps. It supports responsive design by monitoring container width changes against pre-defined breakpoint

Dioxus is a cross-platform development framework designed for building native desktop, mobile, and web applications from a single codebase. It utilizes a declarative component model and macro-powered syntax to define reusable interface elements, which are then rendered as native widgets or web elements. At its core, the framework employs a signal-based reactivity system that tracks state dependencies to trigger granular updates, ensuring efficient interface performance without re-rendering the entire application tree. The framework distinguishes itself through a unified full-stack runtime tha

Iced is a cross-platform graphical user interface framework designed for building interactive applications with a focus on type safety and predictable state management. It utilizes a declarative architecture that separates application state, update logic, and view rendering, allowing developers to construct complex interfaces by nesting reusable functional components. The framework distinguishes itself through an Elm-inspired message-passing pattern, where all user interactions are processed as discrete messages to ensure reliable state transitions. It employs an immediate-mode rendering para

Layui is a web UI component library, frontend layout framework, and CSS asset optimizer. It provides a collection of pre-styled visual elements and layout patterns used to build browser-native web interfaces. The framework enables the composition of structured web pages through standardized design assets and CSS components. It includes tools for compressing stylesheets and resolving imports to improve loading speeds across different web browsers. The library covers web UI development and frontend layout composition, facilitating rapid interface prototyping by assembling functional frontends

UI Kitten is a cross-platform mobile UI library and design framework for building mobile interfaces. It provides a collection of reusable, accessible visual components and layout blocks that strictly follow the Eva Design System specifications. The library features built-in support for dynamic theming, allowing applications to switch between light and dark modes or custom color schemes at runtime. It utilizes a token-based color mapping system and a shared context provider to ensure visual consistency across all screens. The framework includes a library of standardized production-ready eleme

GrapesJS is a modular, web-based visual editor framework designed for building drag-and-drop page builders and custom content management interfaces. It functions as a structural engine that manages hierarchical document models, allowing developers to create reusable design blocks and complex page compositions. By providing a schema-driven approach to UI configuration, the framework enables the construction of design environments where users can assemble layouts and manage component properties visually without writing raw code. The project distinguishes itself through a highly extensible, plug

This framework is a server-side development platform for building interactive, data-driven web applications using Java. It provides a comprehensive component model that allows developers to construct complex user interfaces entirely through backend code, abstracting away the need to manually manage HTML, CSS, or client-side scripting. The platform distinguishes itself by maintaining the application state and user interface hierarchy on the server, synchronizing changes to the browser through a persistent communication channel. This architecture enables developers to bind backend domain object

Compose Multiplatform is a declarative user interface framework that enables the development of native graphical interfaces across desktop, mobile, and web platforms using a single Kotlin codebase. It functions as a multiplatform library that allows developers to share both application logic and UI components while maintaining access to platform-specific features through abstraction layers. The framework utilizes a reactive state management system that automatically tracks data mutations to trigger granular interface updates. By employing a cross-platform rendering engine based on a hardware-

This project is a CSS layout framework that functions as a responsive UI geometry solver. It replaces traditional static box model calculations with a constraint-based engine that determines element positions and dimensions by evaluating relational rules. The engine distinguishes itself by using a system of linear equations to resolve geometric conflicts, ensuring that all spatial constraints are satisfied simultaneously. It utilizes a shorthand visual syntax to define these relationships, allowing developers to describe complex alignment and spacing requirements through a declarative languag

Golden Layout is a framework-agnostic UI container and web window layout manager designed to organize application interfaces into a flexible grid of draggable and resizable multi-pane windows. It functions as a hierarchical grid system that arranges page elements into a tree of nested rows and columns to create complex professional interfaces. The system acts as a multi-window workspace orchestrator, allowing components to be detached from the main layout into independent native browser windows. It also serves as a serializable layout engine that captures the arrangement of user interface com

Simple grid layout library for LÖVE engine (Love2D).

Avalonia is a cross-platform desktop framework that enables the creation of native-feeling applications for Windows, macOS, and Linux from a single codebase. It functions as a declarative UI toolkit, allowing developers to define complex visual hierarchies and interface structures using a markup-based syntax that maps directly to underlying object properties. By utilizing the Model-View-ViewModel architectural pattern, the framework facilitates a clean separation between application logic and user interface layout, which simplifies unit testing and component maintenance. The framework disting

This library is a portable, header-only engine designed for calculating the geometric positions and dimensions of nested rectangular elements. It provides a recursive stacking-box model to determine interface coordinates, serving as a lightweight solution for two-dimensional layout calculations in C99 or C++ environments. The engine distinguishes itself through its focus on portability and resource efficiency. It utilizes a dependency-free memory abstraction that allows developers to override default allocation and assertion routines, making it suitable for specialized or restricted computing