Topic selected: Option A – Purely Technical: "Building a Secure AI Proxy for Browser Tools

This is the strongest choice. It teaches a tangible, highly demanded skill (API key security) with actual code, making the backlink to AfriWidget feel like a natural, neutral citation rather than a sales pitch. Here is the article, rewritten to be strictly technical, objective, and genuinely useful for dev.to readers. Stop Exposing Your AI API Keys: Build a Secure Proxy with Cloudflare Workers We have all seen it. You open the browser's DevTools on a "cutting-edge" AI startup's landing page, check the Network tab, and find a direct POST request to api.openai.com containing a plaintext API key in the headers. It is one of the most common—and dangerous—mistakes in modern web development. Exposing your LLM API key client-side is an open invitation for abuse, leading to stolen credits, hefty bills, and potential account suspension. The standard solution is the Backend-for-Frontend (BFF) proxy pattern. But how do you implement it practically, cheaply, and securely without spinning up a heavy Express server? In this guide, I will walk you through building a lightweight, serverless AI proxy using Cloudflare Workers to securely call Groq (or OpenAI) APIs from your browser-based calculators and tools. The Architecture: How It Works Instead of your frontend talking directly to the AI provider, we introduce a stateless middleware layer: Browser App → Cloudflare Worker (Proxy) → Groq/OpenAI API ↑ ↑ (No API Key) (API Key stored securely in Worker env vars) The Worker's responsibilities: Receive the sanitized calculation context from the frontend (numbers, not PII). Attach the secret API key via environment variables. Forward the request to the LLM provider. Stream or return the generated insight back to the client. Step 1: Scaffolding the Cloudflare Worker We will use the new create-cloudflare CLI. Make sure you have Node.js installed. npm create cloudflare@latest ai-proxy Choose "Hello World" worker and TypeScript. Once inside the directory, install the Groq SDK: npm install gr