My Email Tech Stack for High Retention Brands

By Chris Johnson, Lifecycle and Retention Strategist

Quick take No tech stack replaces strategy. But if you are serious about retention, there are a few tools I will always bring with me. Here is the core email setup I use for brands focused on customer lifetime value.

Introduction

Every brand wants better retention. Fewer churned customers. Higher repeat purchase rates. More loyalty and more profit.

But most brands do not realize how much their tools are limiting their execution.

You do not need dozens of apps. You just need a smart stack built around real lifecycle goals.

Here is what I use when building or upgrading an email program designed for retention.

The ESP: Klaviyo, Braze, or Iterable

No surprise here. These are the three I use and recommend most often. Each serves a slightly different type of brand.

Klaviyo Perfect for Shopify based brands that want strong ecommerce integration, fast execution, and simple flow logic. Ideal for teams without heavy developer support.

Braze Built for real time communication and cross channel messaging. Best suited for app based, mobile first, or content heavy brands. A great fit for larger teams or brands with technical resources.

Iterable Strong all around platform with a clean interface and flexible personalization tools. Especially useful for brands that want catalog based recommendations and easier journey building without a steep learning curve.

I can work with any platform, but these three deliver the fastest value for most ecommerce and subscription based businesses.

Deliverability Insurance: Kickbox

If you are not cleaning your list, you are setting yourself up to fail.

Kickbox checks your list for invalid addresses, spam traps, and other harmful signals. It is the fastest way to protect your sender reputation and make sure your best emails actually reach the inbox.

I recommend running every list through Kickbox before big sends and at least once a quarter for ongoing health.

Testing and Optimization

You do not need ten tools for testing. You just need to commit to a process.

Use your ESP’s built in A and B testing tools for subject lines, send times, and offers.

Then look deeper. Track how those changes impact metrics like second purchase rate, subscription retention, and revenue per recipient.

You do not need more tests. You need more meaningful ones.

Analytics and Insight

For day to day retention KPIs, most ESP dashboards are enough. But if you want to connect email to broader customer behavior, tools like Looker or GA help surface real business insights.

What I track:

• Repeat purchase rate

• Subscription churn (Products and email)

• Revenue by flow

• Traditional Email KPIs (by flow and segment)

• Customer lifetime value by cohort

  
  

These are the numbers that actually matter if retention is the goal.

Final Thought

A great tech stack cannot replace a great message. But it can make your messages land better, convert faster, and scale smarter.

If you are struggling with retention, take a hard look at your tools. Sometimes the biggest fix is not the offer. It is the foundation.

🔹 Want to rebuild your retention tech stack the right way? Reach out to me to book a free audit 

Chris Johnson is a retention and lifecycle strategist who builds high converting email, SMS, and push programs for ecommerce brands. He works across Klaviyo, Braze, Iterable, and custom stacks with a focus on revenue, not vanity metrics.