Show HN: Building a WhatsApp API with 0 markup on Meta pricing

Hey HN, I'm Pau. We've been building Zernio for the past 9 months and we just crossed $1M in ARR (bootstrapped).

Zernio is a unified API for social platforms. One API for Instagram, TikTok, YouTube, LinkedIn, X, and 9 others. Today we're adding WhatsApp.

We've spent 3 weeks just getting a test message to send. Meta requires a developer app, a WhatsApp Business Account inside Business Manager, business verification (2-14 days), phone number OTP, webhook configuration with a two-step subscription, and token management for tokens that die every 60 days. Miss one step and messages vanish with no error.

So we built it so our users don't have to deal with any of that. Connect via Embedded Signup, get an API key, start sending. 37 endpoints covering messaging, broadcasts, templates, contacts, and phone number provisioning.

The pricing model: zero markup on Meta's per-message rates. Most BSPs add 20%+ on top. We charge per account, not per usage.

Docs: https://docs.zernio.com/platforms/whatsapp

Happy to answer questions about WhatsApp API integration or how we got to $1M ARR bootstrapped :)