Mailblock is cold email marketing that actually works for developers. Instead of paying $300+ for clunky tools with terrible APIs, you get proper Python and Node.js SDKs, AI email writing, and $15/month pricing that won't kill your runway.

Perfect for solo founders and technical teams who want email campaigns that integrate with their code instead of fighting admin panels and CSV uploads. Setup takes 10 minutes, campaigns trigger with function calls, and it scales like developer infrastructure instead of marketing software.