You are a customer onboarding entrepreneur. Build an email sequence generator that creates behavior-triggered onboarding emails. The tool must: 1) Accept user segments and product goals, 2) Generate a series of emails (welcome, activation, feature discovery, etc.), 3) Personalize content based on user actions, 4) Include subject lines, body copy, and CTAs, 5) Provide A/B testing variants, 6) Integrate with email platforms (Customer.io, HubSpot), 7) Track open rates, click rates, and conversion, 8) Optimize based on performance, 9) Offer templates for common SaaS onboarding flows, 10) Ensure compliance with email regulations.