Building Svelte Apps from InVision Prototype Videos

TL;DR: Replay leverages video analysis and Gemini to build fully functional Svelte applications directly from InVision prototype videos, drastically accelerating development and bridging the gap between design and code.

The handoff from design to development is broken. Static prototypes, no matter how polished, are just that: static. They lack the dynamic behavior and user interaction that defines a real application. This often leads to misinterpretations, rework, and ultimately, delays. Forget painstakingly translating InVision prototypes into Svelte code manually. There's a better way.

The Problem with Traditional Design Handoff#

Designers meticulously craft user experiences in tools like InVision. Developers then attempt to recreate that vision in code. The problem? Prototypes are often ambiguous. They show what the UI should look like, but rarely how it should behave.

This disconnect results in:

• •Misinterpretations: Developers guessing at intended functionality.
• •Rework: Code needing to be rewritten to align with the designer's true vision.
• •Slow Development Cycles: Tedious manual translation of designs into code.
• •Lost Context: The original intent behind design decisions gets diluted.

Screenshot-to-code tools offer a partial solution, but they fall short. They can only reconstruct what they see, not what the user does. They can't capture the dynamic interactions and state changes that are crucial for a functional application.

Behavior-Driven Reconstruction: Video as the Source of Truth#

Imagine if you could record a video of someone interacting with your InVision prototype and automatically generate a working Svelte application. That's the power of behavior-driven reconstruction.

Replay analyzes video, not just screenshots. It understands user behavior, identifies UI elements, and reconstructs the application's logic. This approach offers several key advantages:

• •Captures Dynamic Behavior: Replay understands clicks, scrolls, form submissions, and other user interactions.
• •Eliminates Ambiguity: The video provides a clear and unambiguous record of the intended functionality.
• •Accelerates Development: Code generation is automated, freeing up developers to focus on more complex tasks.
• •Preserves Design Intent: The original vision is faithfully translated into code.

Replay: Bridging the Gap Between Design and Code#

Replay is a video-to-code engine that leverages Gemini to reconstruct working UI from screen recordings. It uses behavior-driven reconstruction, making video the source of truth. Forget static prototypes and manual coding. Replay allows you to build Svelte apps directly from InVision prototype videos, dramatically accelerating your development process.

Here's how Replay stacks up against traditional methods and other code generation tools:

Replay understands what users are trying to do, not just what they see. This is a game-changer for building complex, interactive applications.

Building a Svelte App from an InVision Prototype Video: A Step-by-Step Guide#

Let's walk through the process of building a Svelte application from an InVision prototype video using Replay.

Step 1: Record Your InVision Prototype#

Record a video of yourself (or a user) interacting with your InVision prototype. Make sure to demonstrate all the key user flows and interactions. The clearer the video, the better the generated code will be.

💡 Pro Tip: Narrate your actions while recording the video. This can provide valuable context for Replay's analysis.

Step 2: Upload the Video to Replay#

Upload the recorded video to the Replay platform. Replay will automatically analyze the video and identify the UI elements and user interactions.

Step 3: Review and Refine the Generated Code#

Replay will generate a Svelte application based on the video analysis. Review the generated code and make any necessary refinements.

svelte
<script>
  let count = 0;

  function increment() {
    count += 1;
  }
</script>

<button on:click={increment}>
  Clicked {count} {count === 1 ? 'time' : 'times'}
</button>

This simple Svelte component demonstrates how Replay can automatically generate interactive UI elements from a video. The code includes event handling (

) and dynamic data binding ().

Step 4: Integrate with Supabase (Optional)#

Replay seamlessly integrates with Supabase, allowing you to easily add backend functionality to your Svelte application. Configure your Supabase credentials in Replay, and the generated code will automatically include the necessary database interactions.

typescript
// Example of fetching data from Supabase
import { supabase } from './supabaseClient';

const fetchData = async () => {
  const { data, error } = await supabase
    .from('items')
    .select('*');

  if (error) {
    console.error('Error fetching data:', error);
    return [];
  }

  return data;
};

This code snippet demonstrates how Replay can generate code that interacts with your Supabase database. It fetches data from a table named "items" and returns the results.

Step 5: Deploy Your Svelte App#

Once you're satisfied with the generated code, you can deploy your Svelte application to any hosting platform.

Key Features of Replay#

• •Multi-Page Generation: Replay can generate multi-page Svelte applications from a single video.
• •Supabase Integration: Easily integrate your Svelte app with Supabase for backend functionality.
• •Style Injection: Replay can automatically inject styles into your Svelte components, based on the visual appearance of the InVision prototype.
• •Product Flow Maps: Replay generates visual flow maps illustrating user journeys through your application.

📝 Note: Replay currently supports a subset of Svelte features. We are continuously expanding our support to cover more complex scenarios.

The Future of Design Handoff#

Replay represents a paradigm shift in the way we approach design handoff. By leveraging video analysis and AI, we can bridge the gap between design and code, accelerating development and ensuring that the final product accurately reflects the designer's vision.

⚠️ Warning: While Replay automates much of the development process, it's important to remember that it's a tool, not a replacement for skilled developers. Review and refine the generated code to ensure quality and maintainability.

Frequently Asked Questions#

Is Replay free to use?#

Replay offers a free tier with limited features. Paid plans are available for more advanced functionality and higher usage limits. Check our pricing page for details.

How is Replay different from v0.dev?#

While both tools aim to accelerate UI development, Replay focuses on video input and behavior-driven reconstruction. v0.dev primarily uses text prompts and relies on static design information. Replay understands user intent from video, leading to more accurate and functional code generation.

What kind of InVision prototypes work best with Replay?#

The best results are achieved with interactive prototypes that clearly demonstrate user flows and interactions. Prototypes with well-defined UI elements and consistent styling will generally produce better code.

What if the generated code isn't perfect?#

Replay is a powerful tool, but it's not magic. The generated code may require some refinement. Think of it as a great starting point that saves you significant time and effort.

Does Replay support other UI frameworks besides Svelte?#

Currently, Replay primarily supports Svelte. We plan to expand our framework support in the future. Stay tuned for updates!

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Ready to try behavior-driven code generation? Get started with Replay - transform any video into working code in seconds.