Prototype: What is a prototype?

What is a prototype?

A prototype is an interactive, simulated version of a digital product (website, mobile application, software) that allows users to navigate between screens, click buttons and experience something close to the final product, without a single line of code being written. The prototype transforms static mockups into a navigable interaction flow that reveals the strengths and weaknesses of the design.

Prototyping is a critical step in the UX design process, sitting between wireframing and development. It allows design hypotheses to be tested with real users, concrete feedback to be collected and rapid iteration to take place before committing the costly resources of development. At KERN-IT, the KERNWEB division uses Figma to create high-fidelity interactive prototypes that are presented to clients and tested by target users.

Why prototyping matters

Prototyping delivers considerable value at every stage of the design cycle. It reduces risk, accelerates decision-making and improves the quality of the final product.

• Validation before development: testing a prototype costs a fraction of modifying an already-developed product. Every issue identified during prototyping represents a significant saving during development.
• Stakeholder communication: an interactive prototype is infinitely more expressive than a written specification or static mockup. Clients and decision-makers can experience the product first-hand and give precise feedback.
• Realistic user testing: prototypes enable usability tests to be conducted under near-real conditions. Participants quickly forget they are testing a prototype and behave naturally.
• Team alignment: the prototype serves as a shared reference between designers, developers and product owners. It eliminates ambiguity and conflicting interpretations.
• Rapid iteration: modifying a prototype is significantly faster than modifying code. Iteration cycles are short, allowing more solutions to be explored.

How it works

The prototyping process starts from wireframes or high-fidelity mockups to create a navigable interactive experience. At KERN-IT, we use Figma exclusively for prototyping, ensuring seamless integration with the wireframing and design phases.

A low-fidelity prototype links wireframes together through simple navigation connections. The goal is to test the logic of the user journey: can users find the information they need? Is the number of steps to reach a goal reasonable? This type of prototype is ideal for exploratory testing early in a project.

A high-fidelity prototype reproduces the final visual appearance of the product with animated transitions, micro-interactions and realistic content. It is virtually indistinguishable from the finished product for a casual user. This level is used for formal usability tests and client presentations before final sign-off.

KERN-IT Figma prototypes include documented flows that map all user journeys: the primary journey, alternative paths and error handling. Each screen is connected to the next through defined interactions (click, hover, drag) with specified transitions (fade, slide, dissolve).

Concrete example

KERN-IT is commissioned to design an online booking platform for a Belgian hotel chain. The booking process has five steps: date selection, room choice, additional options, personal information and payment.

The KERNWEB team creates a complete high-fidelity prototype in Figma that simulates the entire booking journey. Each step is interactive: a calendar allows date selection, room cards display prices dynamically and a summary updates in real time. The prototype is tested with eight representative users.

Testing reveals two major issues: users do not notice the date modification button on the summary screen, and the personal information form is perceived as too long. The team modifies the prototype in 45 minutes, retests with three additional users and validates the solution. Development on Wagtail CMS and TailwindCSS can then begin on solid foundations.

Implementation steps

1. Define the journeys to prototype: identify critical flows that need validation (purchase journey, registration, search, etc.).
2. Prepare the screens: ensure that mockups or wireframes for each screen are ready in Figma.
3. Define interactions: for each clickable element, specify the destination screen, interaction type (click, hover) and transition (fade, slide).
4. Add micro-interactions: for high-fidelity prototypes, integrate animations that enrich the experience (dropdown menus, loading states, notifications).
5. Test internally: have the project team walk through the prototype to detect missing links and inconsistencies.
6. Conduct user tests: organise testing sessions with representative users, observe behaviours and document friction points.
7. Iterate and validate: modify the prototype based on feedback, retest if necessary and obtain sign-off before moving to development.

Related technologies and tools

• Figma: the central prototyping tool at KERN-IT, offering advanced interactive prototyping, real-time collaboration and client sharing capabilities.
• Wagtail CMS: the Django-based CMS used for final development. The validated prototype serves as an exact reference for template and component implementation.
• TailwindCSS: the CSS framework that faithfully translates prototyped interactions and layouts into performant front-end code.

Conclusion

Prototyping is the step that transforms design ideas into testable experiences. It allows usability problems to be discovered and fixed before they become costly bugs in production. At KERN-IT, the KERNWEB division views prototyping as an investment, not a cost: every euro invested in a Figma prototype saves ten during development and maintenance.