This article is written in partnership with Webix, a rich JavaScript library of UI components.

When starting a new project, one of the most important decisions developers face is choosing the right approach to building the user interface, balancing business requirements, design, performance, scalability, and time constraints. With the growing number of modern frontend technologies available, the decision can be overwhelming.

Typically, there are two options: building everything from scratch or using prebuilt UI components. While custom coding offers full control and a unique UI, it requires significant effort to implement even basic elements like data tables or dropdowns, ensuring functionality, accessibility and cross-browser compatibility. Therefore, many developers incline to the second option and use in their work prebuilt UI libraries and components.

Today, we can see that two distinct approaches available in frontend UI libraries:

• styled UI components - provide both functionality and style bundled together (e.g. like SVAR for Svelte and React or Webix JavaScript library);
• unstyled/headless components - reusable blocks of functionality that give you full control over the visual representation.

In this article, we’ll mention the differences between styled and unstyled/headless components, compare their use cases, and help you to make the right choice for your project. Along the way, we’ll introduce how SVAR and Webix components leverage the styled approach to simplify development and enhance productivity.

Styled UI Components

Styled components are “ready-to-use” UI elements that come with built-in styles, logic, and sometimes predefined user experience (UX) patterns. They are designed to simplify and speed up the development process, allowing developers to focus on functionality rather than design details.

Examples: Webix, SVAR components, MUI for React, Chakra UI, Kendo UI, React Bootstrap.

Advantages:

• Quick prototyping and development: styled components are ready to use right out of the box. This makes them ideal for rapid development projects with tight deadlines.
• Consistency: pre-styled components adhere to established design systems, ensuring a consistent look and feel across the application.
• Ease of use: with minimal configuration, developers of all skill levels can quickly integrate these components into their projects.

Disadvantages:

• Limited customization: predefined styles can be challenging to override, especially if your project requires a unique, highly-customized design.
• Overloading: styled components may include unnecessary features or styles that aren’t relevant to your use case, potentially overloading your project and making the bundle size heavier.

When to use:

• In generic-looking, internal apps
• When you have fixed time and resources constraints
• Rapid prototyping and MVP development
• Enterprise and large-scale applications with multiple teams
• Projects with limited design resources
• Startup projects with tight timelines

Unstyled or Headless UI Components

If you need to stick to the specific design it can be quite challenging to customize somebody’s CSS code so the UI looks exactly how you need. What if you have a highly customized, polished design system you need to implement?

This is where headless or unstyled components come to the forefront. They provide only the underlying functionality and logic without any visual design. They offer maximum flexibility, making them ideal for projects where customization is a priority. However, this approach requires more effort and needs a designer in your team to define the entire look.

You can also pair the unstyled components with CSS frameworks like Tailwind CSS, which give you utility-first classes to rapidly style components while maintaining control over the design.

Examples: With the growing demand for unique, personalized designs, we can see the rise of unstyled component libraries in recent years, like Headless UI, Radix UI, React Aria or shadcn/ui. And even well-known UI libraries have introduced their unstyled versions, e.g. Base UI from MUI, unstyled mode of PrimeReact and KendoReact libraries.

Advantages:

• Full customization: headless components give you complete control over the design and behavior, making them perfect for highly customized or branded interfaces.
• Scalability: these components are helpful in large-scale, branded projects where precise alignment with design systems or style guides is crucial.
• Flexibility: seamless adaptation to any design system or framework.
• Lightweight: since unstyled components don’t bundle unnecessary styling or design-related logic, they often have smaller file sizes and lower runtime overhead.

Disadvantages:

• Complexity: building UI with headless components requires more time, advanced skills, and effort compared to styled components.
• Complicated reusability: since each implementation is customized, you may end up duplicating effort when working on multiple projects.
• Dependency on design: you need a robust design system or a designer on your team to ensure a consistent and polished look.
• Steeper learning curve: developers must have a strong understanding of CSS and design principles, as well as familiarity with the specific headless library being used. This makes onboarding more complex for junior developers or those unfamiliar with the approach.

When to use:

• Complex, unique design systems
• Highly branded interfaces
• Large, brand-critical enterprise applications
• Projects requiring pixel-perfect custom designs
• Multi-product design consistency
• Performance-critical applications

How SVAR and Webix Approach Styling

Both SVAR and Webix take a styled component approach, making it easier for developers to build user interfaces quickly and consistently.

Webix components come pre-styled with dimensions and spacings defined in JavaScript. While this ensures a polished and consistent look, it can be challenging to adapt these styles for projects requiring unique designs. But for developers, it’s easy to start with a good-looking component library and build user interfaces with a unified, consistent look and feel.

SVAR introduces a more flexible approach to styling the components by leveraging CSS variables for maximum customization without compromising ease of use. This gives developers control over:

• Dimensions: heights, widths, and spacings can all be adjusted via CSS, eliminating the need to touch JavaScript logic.
• Colors and themes: modify color schemes effortlessly by updating a few CSS variables, making it easy to align SVAR components with your brand or application theme.
• Customizability: developers can fine-tune taskbars, grids, or any other UI elements without battling against hardcoded styles or specificity issues.

Conclusion

Choosing between styled and unstyled (headless) UI components depends on your project’s requirements, resources, priorities, and preferences. Styled components, like SVAR and Webix, are ideal for projects with tight deadlines, limited design resources, and a need for consistent, polished UI elements.

On the other hand, unstyled components offer incomparable flexibility, making them a good choice for building highly customized, branded, and performance-critical applications.

SVAR components strike a middle ground between the strict, predefined nature of Webix and the total flexibility of headless components. By allowing key design aspects to be adjusted through CSS variables, SVAR offers highly customizable UI components for Svelte and React, while providing the ease of use and powerful, prebuilt functionality.