Free 3-Day Email Course

Your LTV:CAC Ratio Is Lying to You. This Course Shows You How.

A free email course on the backend retention triggers that subscription businesses miss — plus the full 90-Day Retention Engineering Blueprint (PDF) on Day 3.

Delivered over 3 days. Then The Perennus Letter every Tuesday. Free. Unsubscribe anytime.

What You'll Learn

3 Days. 3 Retention Truths Most Teams Never See.

Each day delivers one infrastructure-level insight — the kind of thinking that turned a 13.3% onboarding rate into 60.2% and recovered $150K+ in annual revenue for a single workspace.
Day 1
Why blended LTV:CAC ratios hide cohort-level cash bleeding
The number your board sees is an average. Averages hide the cohorts that are bleeding. You'll learn how to decompose blended ratios and find the retention decay that's invisible at the aggregate level.
Day 2
The 3 backend triggers that stop retention decay at the infrastructure level
Most teams treat retention as a campaign problem. It's an infrastructure problem. You'll get the three trigger architectures that catch revenue leaks before they compound — at the system level, not the email level.
Day 3
Your Retention Debt score + the full 90-Day Blueprint
A framework for scoring your own retention infrastructure — and the full 90-Day Retention Engineering Blueprint (PDF) with every framework, architecture, and playbook behind the results in our case studies.
Includes PDF Blueprint
After the Course

Then You Get The Perennus Letter. Every Tuesday.

Teardowns of real companies and their lifecycle systems. Automation architectures you can steal. Operator-level insights you cannot Google.
🔬
Teardowns
Deep behavioral autopsies of how companies like Notion, Canva, and Duolingo engineer retention at scale. Real systems. Real findings.
⚙️
System Architecture
How to build lifecycle infrastructure that compounds — trigger logic, data property design, and always-on monitoring frameworks.
📊
Operator Insights
Lessons from real engagements. What broke, what we fixed, and the revenue impact — with the math to prove it.
🩺
Back Half Diagnostics
Frameworks for auditing your own post-signup infrastructure — onboarding, deliverability, re-engagement, and trigger integrity.
Testimonials

What clients actually say.

"Isaac identified issues in our lifecycle infrastructure we'd been missing for months. The improvement was immediate and measurable."

Genevieve Bellaire
Genevieve Bellaire
Founder, Realworld
★ ★ ★ ★ ★

"What impressed me most was the depth of his thinking around retention. Instead of jumping straight into tactics, he analysed our entire customer journey and connected that with lifecycle messaging in a way that made complete sense."

Monica Anyango
Monica Anyango
Founder, Simplicity & Productivity Co.

"Isaac turned what felt like a messy problem into a clear system. He mapped our onboarding journey, showed us exactly where users were dropping off, and delivered email flows ready to launch immediately."

Abimbola Ajibade
Abimbola Ajibade
Co-founder, Kitov Consult
Nathan Barry, Founder of Kit, responding to a Perennus lifecycle teardown on LinkedIn

From a single workspace scan: 66,000 contacts analyzed. 32% invalid emails identified. 74% inactive contacts flagged. A broken behavioral trigger silently queuing 174,000 emails — zero delivered. That same diagnostic framework now runs inside Perennus, automatically, every 6 hours.

Before — Deliverability Breakdown
Customer.io deliverability report showing 56.3% Gmail bounce rate, 80.8% Yahoo bounce rate
After — Deliverability Restored
Customer.io deliverability report showing 2.1% Gmail bounce rate, 0% Yahoo bounce rate
Start the Free Course

The revenue layer most teams ignore is the one that compounds.

3 days. 3 retention truths. The full 90-Day Blueprint. Then weekly operator-level intelligence every Tuesday.