We built Simplex because we kept getting scary invoices.

Simplex AI started as an internal tool. We were shipping vibe-coded side projects, and every one of them had the same problem: 80% of the AI calls were tiny structured tasks — categorize this ticket, extract this JSON, route this request — and yet the bill looked like we were running a research lab.

So we built a small, fast runtime tuned for those exact calls, wrapped a flat monthly price around it, and pointed it at the OpenAI SDK we already had. Our own bills dropped by about 40%. Then we made it available to everyone else shipping vibe-coded apps.

No frontier claims. No token surprises. Just predictable, boring, cheap inference for the boring, structured tasks that make up most of your product.