image-altext is a lightweight TypeScript microservice built with Hono on Cloudflare Workers that generates accessible alt text and SEO captions from image URLs or uploads. It runs vision inference at the network edge and caches structured JSON responses in Cloudflare KV for instant repeat lookups.
$ npx wrangler deploy
import { Hono } from 'hono';
const app = new Hono<{ Bindings: { AI: Ai } }>();
app.post('/api/alt', async (c) => {
const { url } = await c.req.json<{ url: string }>();
const res = await fetch(url);
const image = [...new Uint8Array(await res.arrayBuffer())];
const out = await c.env.AI.run('@cf/unum/uform-gen2-qwen-500m', {
image,
prompt: 'Describe this image concisely for a screen reader.'
});
return c.json({ url, alt: out.description.trim() });
});
export default app;Repository: https://github.com/bhubbard/image-altext
Live Studio: https://code.brandonhubbard.com/image-altext/
Portal: https://code.brandonhubbard.com/
Install: npm run deploy
Design System: Brandon Hubbard Swiss Modernist (#0A0A0C / 1px Exposed Structural Grid)