Vaadin Alternatives

Tailwind CSS is a customizable, low-level HTML & CSS framework. With Tailwind CSS you can create unique UIs without having to write any CSS. The framework comes with pre-written CSS classes that you can add to HTML elements to build bespoke UI components, your way.

A free and open-source HTML and CSS framework dedicated to responsive and mobile-first frontend web development. With Bootstrap developers can get up and running fast without writing boilerplate HTML and CSS. Bootstrap comes packed with design templates and standards for buttons, forms, navigation, typography and interface components. The framework also provides extra interactive JavaScript extensions written specifically for Bootstrap.

Material UI is a free and open-source framework with React components for faster and easier web development. With Material UI you can build your own design system and get started with Material Design. The framework includes pre-built React components for almost all UI use-cases that are at your fingertips as soon as you install Material UI.

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A framework designed to make it easy to build web applications with Java & Scala.  The Play Framework is is based on a lightweight, stateless, web-friendly architecture that follows a model-view-controller (MVC) pattern. While providing predictable and minimal resource consumption (CPU, memory, threads) suitable for highly-scalable applications.  Play is written in Scala and can be used for all programming languages that can be compiled into JVM bytecode.

With Webix you can create rich user interfaces and frontend applications using JavaScript, HTML and CSS. It's a web-based UI design tool for developing complex and dynamic, cross-platform web applications. Webix allows you to design better user experiences, using drag and drop functionality and utilizing over 100 pre-built UI components and widgets.

Grails is powerful Groovy-based web application framework for the JVM built on top of Spring Boot.

Apache Wicket is a free and open-source, Java-based component oriented web application framwork. With Apache Wicket you can quickly create web well structured, component-based web applications. Apache Wicket is used by governments, stores, universities, cities, banks, email providers across the globe.