Customer.io Lifecycle System. 500k+ Monthly Messages

Customer.io Lifecycle Marketing. Email Automation System: 80+ Active Campaigns, 7 Channels, 500k Monthly Messages

I built a Customer.io email automation and lifecycle marketing system that moves hundreds of thousands of users through the complete customer lifecycle: from first action, to paid conversion, to long-term retention, without breaking as the platform scaled. The brief wasn't "send better emails." It was marketing automation infrastructure.

82 concurrent lifecycle campaigns running in production simultaneously, built and managed inside Customer.io across 7 delivery channels: email, push, webhook, Slack, in-app, SMS, and browser. This is multi-channel marketing automation, not a single email sequence. Every campaign is tied to a specific behavioral trigger (a document published, an upload completed, a trial started), firing the right triggered email at the right moment without manual intervention.

The email automation system covers every stage of the lifecycle: multi-cohort onboarding email sequences for university students and content contributors, mid-funnel engagement campaigns for active users, monetisation and upgrade flows converting free users to Premium, and re-engagement / win-back campaigns for users going dormant. This is full-funnel lifecycle marketing, covering onboarding, activation, conversion, and retention in one connected system.

Alongside the campaign layer, I built the full Design Studio: 1,158 email templates with dynamic personalisation using Liquid logic, A/B test frameworks across subject lines and send times, and a broadcast email infrastructure now supporting 3,100+ newsletter campaigns. Combined, this covers behavioral email automation, transactional email, and broadcast/newsletter email under one architecture.

5.15M+ messages delivered through the onboarding automation alone

30–38% open rates on core lifecycle engagement campaigns (industry average: 20%)

61.4% conversion rate on the Premium upgrade automation

505,035 messages sent from a single behavior-triggered campaign

48.7% open rate on broadcast newsletters at 31k+ recipients

This isn't a campaign. It's email marketing automation infrastructure built for scale: the kind that earns revenue every hour, with or without anyone actively running it.