Open-source alternatives to Engine

Packery is a JavaScript bin-packing grid layout engine and DOM element positioning library. It arranges elements of varying sizes into a gapless, compact grid by calculating and applying absolute coordinates to HTML elements to prevent overlapping. The library enables the creation of draggable grid interfaces, allowing users to rearrange elements via drag-and-drop while the system automatically reflows the remaining items. It maintains stable, responsive layouts across different screen dimensions by using a percentage-based positioning system and responding to window resize events. The tool

Terminal.Gui is a cross-platform .NET toolkit for building interactive text-based user interfaces. It provides a component-based architecture, a terminal rendering engine, and a declarative layout system to create console applications that run consistently across Windows, macOS, and Linux. The framework distinguishes itself with a comprehensive set of interactive console widgets, including data grids, hex editors, and hierarchical tree components. It supports advanced visual capabilities such as 24-bit True Color, Sixel image support, and a relative-coordinate layout system that adapts to ter

This project is a curated collection of technical questions and answers designed to assist developers in preparing for software engineering interviews within the iOS ecosystem. It serves as a structured study tool for evaluating proficiency in mobile application architecture, system design, and core programming concepts. The repository provides a comprehensive reference for essential development topics, including memory management, concurrency, design patterns, and data persistence. By covering these foundational areas, it enables users to review common industry interview subjects and test th

Makie.jl is a high-performance Julia data visualization library and hardware-accelerated plotting engine used to create interactive 2D and 3D visualizations. It functions as a reactive visualization framework where plots update automatically via observables and compute graphs, and as a vector graphics generator for high-resolution academic output. The system is distinguished by its backend-agnostic rendering pipeline, which supports OpenGL, WebGL, and ray-traced scenes. It employs a grammar-of-graphics approach to map variables to aesthetic attributes and utilizes a hierarchical scene graph t

This project is a curated study guide and knowledge base designed to assist software engineers in preparing for technical interviews within the iOS development ecosystem. It provides a structured collection of questions and answers focused on Swift and Objective-C, serving as a comprehensive reference for mastering the core concepts required for professional technical assessments. The repository distinguishes itself by bridging the gap between theoretical knowledge and practical application. It covers essential industry-standard practices, including architectural patterns, memory management s

toolong is a terminal log viewer and TUI log manager designed for monitoring live log streams and navigating large log files. It functions as a log aggregator and JSONL formatter, capable of merging multiple log files into a single chronological view by automatically detecting timestamps. The application supports the visualization of structured data by pretty printing JSONL files and applying syntax highlighting to common web server log patterns. It handles large-scale data efficiently through virtual-sized scrollable views, allowing users to open compressed logs or files of any size without

This project is a scientific visualization guide and data visualization framework designed for creating high-quality 2D and 3D figures for academic journals and scientific publishing. It provides a structured approach to designing precise layouts, coordinate systems, and typography for complex scientific data. The project features a specialized print-ready PDF workflow and a CMYK print production workflow. These systems translate digital RGB colors into printer-specific CMYK profiles to ensure visual accuracy for physical hardcover and softcover printing. It also serves as a guide for SVG dat

Textual is a Python TUI framework and asynchronous UI library used to build interactive text user interfaces. It provides a component-based architecture for creating cross-platform applications that run in both terminal and web browser environments. The framework distinguishes itself by utilizing a CSS-based layout engine to apply visual styles to widgets and a command palette interface for discovering and executing application functions. It also supports hosting terminal-based interfaces on the web to enable remote access via a standard browser. The toolkit covers a broad range of capabilit

This project is a Markdown-driven presentation engine that transforms Markdown text into structured, web-based slideshows. It functions as a browser-based presentation tool that renders content with automatic scaling to maintain consistent layouts across different screen resolutions. The framework allows for custom visual layouts and global styles through the use of Markdown templates and CSS. It includes a dedicated presenter view interface that provides formatted speaker notes to keep the presenter synchronized with the audience. The system covers the end-to-end workflow of slide deck crea

Ratchet is a web-based mobile UI framework and component-based library designed to create responsive mobile application interfaces. It provides a CSS mobile layout system that allows for the development of application frontends using standard web technologies. The framework focuses on mobile app interface design and rapid prototyping, utilizing pre-styled visual elements to ensure consistent styling across various screen sizes and resolutions. The system employs a CSS-only approach to define interactive states and layouts, incorporating a grid-based responsive layout and utility-first styles

Webstudio is a visual CMS and website builder that provides a visual development environment for designing and publishing websites. It functions as an AI-powered design tool, a REST and GraphQL API client, and an atomic CSS compiler. The platform distinguishes itself through generative AI capabilities for creating layout variants and refining visual styles from text prompts. It integrates a headless CMS workflow that maps external data sources to visual components and utilizes a specialized compiler to convert design tokens into deduplicated atomic CSS for optimized page load speeds. The sys

Marp is a markdown presentation framework and slide generator that converts structured text into visual slide decks. It functions as a system for creating presentations by identifying specific page-break delimiters within markdown source files. The tool features a command line interface for automating the generation of slide decks within build pipelines. It utilizes a CSS-based styling system, allowing for custom visual formatting through embedded style rules, external stylesheets, and variable theme injection. The framework supports exporting presentations into multiple formats, including P

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

react-native-reusables is a cross-platform mobile UI library and an accessible component kit used to build consistent interfaces across different screen sizes. It functions as a Tailwind CSS component library, providing pre-styled interface elements that utilize utility classes for styling and layout. The project enables cross-platform UI development for iOS and Android through a shared set of reusable visual components. It supports mobile interface prototyping and the creation of cohesive design systems by utilizing standardized, themeable interface elements to maintain uniform branding. Th

SnapKit is a declarative layout library and domain-specific language for managing user interface constraints and view relationships in Swift. It serves as a programmatic framework for positioning and sizing interface elements on iOS and macOS by wrapping native Auto Layout calls in a concise syntax. The library provides a fluent interface that translates high-level descriptive language into imperative layout rules. It differentiates itself through automatic constraint tracking and lifecycle management, allowing for the bulk removal and replacement of positioning rules without manual tracking

gui.cs is a .NET terminal user interface toolkit and framework used to build interactive, cross-platform text-based applications. It provides a structured system for composing terminal views using a view hierarchy and a dedicated layout engine. The library distinguishes itself through a component-based widget system and a constraint-based layout engine that allows interfaces to remain responsive across different terminal window dimensions. It employs a virtual-screen buffer to minimize flickering during redraws and uses state-driven theme configurations to maintain persistent visual styles.

Ratatui is a terminal rendering engine and library for the Rust language used to build interactive text-based user interfaces. It provides a framework for creating command-line dashboards and visual applications by rendering widgets and layouts directly to a terminal screen. The project utilizes a backend-agnostic interface to decouple UI logic from terminal drivers and employs a constraint-based layout engine to divide screen space into nested rectangular areas. It manages rendering through an immediate-mode drawing loop and a buffer-based system to minimize screen flicker. The library supp

nanogui is a native C++ toolkit for rendering interactive user interface components directly within an OpenGL graphics context. It functions as a cross-platform widget library and immediate-mode framework used to create windows, buttons, sliders, and input fields. The toolkit provides specialized capabilities for building technical interfaces, including real-time parameter control panels and custom tooling for graphics-heavy software. It ensures visual consistency across different operating systems and screen resolutions through DPI-aware coordinate scaling. The framework includes a constrai

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

iOS9AdaptationTips is a collection of technical strategies and guides for adapting mobile applications to the iOS 9 operating system. It serves as a development resource for implementing system integration, UI layout adaptations, and push notification configurations. The project provides specific guidance on flexible interface implementation, including support for split-screen modes, dynamic text scaling, and status bar configurations. It also covers the use of secure certificates and heartbeat signals to maintain persistent connection stability for push notifications. The material covers br

Isotope is a JavaScript grid layout library used to create filterable and sortable grids with automatic element positioning in the browser. It functions as a layout engine that calculates absolute coordinates for elements to maintain a dense grid regardless of individual item dimensions. The library features a masonry layout engine that arranges items of varying heights into a compact grid to eliminate vertical gaps. It includes a coordinate-based layout animator for smooth transitions during layout shifts and a CSS selector filtering tool to show or hide elements without reloading the page.

SDAutoLayout is an iOS UI layout framework and programmatic wrapper library. It provides an auto layout constraint engine and tools for managing view dimensions and positions within the Apple iOS user interface ecosystem. The project features a dynamic content height calculator and a simplified syntax for defining layout constraints to reduce boilerplate code. It includes specialized utilities for automatically determining and caching the height of table cells and labels based on their internal text content. The framework covers a range of layout capabilities, including automatic content siz

SwiftEntryKit is a Swift presentation framework and UI overlay library used to orchestrate banners, pop-up views, and custom modal presentations on top of an iOS application window. It functions as a view orchestrator that manages the lifecycle, animations, and layering of multiple overlapping user interface elements. The framework features a priority-based queueing system to determine the display order and precedence of overlays, ensuring specific elements can override others. It includes a dedicated animation toolkit for translation, scale, and fade transitions, alongside haptic integration

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

Taffy is a layout engine that calculates the size and position of user interface components. It is a language-agnostic tool that computes element geometry using Flexbox and Grid algorithms. The engine operates on custom tree structures and node storage through a trait-based interface. This design allows it to be integrated into various programming languages and custom memory management systems. The system handles UI layout computation, including leaf node measurement and floating point pixel snapping to prevent blurring on displays. It utilizes layout result caching to avoid redundant calcul

Grommet is a React UI framework and accessible component library designed for building themed user interfaces. It provides a responsive design system and a themed interface toolkit to ensure inclusive user experiences across various screen sizes and device orientations. The framework emphasizes accessible UI development by providing pre-styled elements that follow web accessibility standards for screen readers and keyboard navigation. It enables the implementation of custom themes through a centralized system that manages visual styles and design tokens. The toolkit covers responsive web des

JazzHands is a UIKit framework providing a scroll-driven animation engine and a paging layout manager. It enables the binding of view properties to timelines of keyframes, allowing visual transitions to be synced with real-time scroll offsets or gesture data. The project distinguishes itself through a value-interpolation engine that calculates intermediate property states. This allows animation progress to be driven by external input values, mapping view attributes to a timeline based on a floating point progress indicator. The framework also includes a system for organizing views within pag