Im tired opening Figma or Photoshop just to post a simple Instagram carousel. The layers, the alignment, the manual exporting—it’s a massive friction point for a developer who just wants to share thoughts quickly. I wanted a tool where I could paste a JSON or a prompt and get a 10-slide deck ready for upload in seconds.

So, I built it. Here’s the breakdown of IG Post Builder, the tech stack, and how I used Claude as a senior pair programmer to ship it in record time.

 

The Core Concept: Prompt-to-Product

The goal was simple: Zero backend, zero login, 100% privacy. I started with a messy single-file HTML prototype to test the logic. Once the "bones" worked, I used Claude to refactor the entire mess into a professional codebase. We iterated through screenshots and error logs until it was a polished Vue 3 SPA.

The Tech Stack:

  • Framework: Vue 3 (Composition API) + Vite for instant hot-reload.
  • State Management: Pinia (handling slide data across the app).
  • Persistence: localStorage for auto-saving. Close the tab, come back later, and your draft is still there.
  • Rendering: html2canvas for high-res 2x PNG exports.
  • Security: Custom XSS sanitization for <span> tags (color highlights).

Key Features for Content Creators

I didn't want a generic editor. I wanted a system that handles the heavy lifting.

  • 8 Modular Layouts: From "Classic" and "Split Card" to "Statement + Image." Mix and match layouts within a single carousel.
  • The AI Workflow: A built-in modal with structured prompt templates. Copy to Claude/ChatGPT, get the JSON, and paste it back. All slides auto-generate in seconds.
  • One-Click Themes: Toggle between Violet Dark, Azure Tech, Emerald SaaS, or Startup Orange. Brand consistency, instantly.
  • Export to ZIP: One click renders every slide and bundles them into a ZIP file ready for upload.

Why It’s Free & Private

Most "free" tools are lead magnets. This isn't one of them.

  • No Login: Start building immediately.
  • No Tracking: I don't want your data. Everything stays in your browser's localStorage.
  • Client-Side Only: Your images are rendered locally, not on a server.

Try It Out

If you’re tired of the "Figma Tax" just to post to social media, give this a spin. It’s built by a developer, for developers and creators who value speed over fancy layers.

 Launch IG Post Builder