Customer.io Case Study: 200+ Scalable Email Templates
Lifecycle
An automated messaging platform for tech-savvy marketers
Customer.io, an automated messaging platform, needed help with the functionality of the email templates. The company discovered customers who built complex designed templates experienced performance and scalability issues. Customer.io sought a partner that could help them identify the problems within their HTML structure and rebuild the template’s foundation to support mass production of templates, integrating dynamic content and flexible coding.
Lifecycle

Key Performance Metrics
200%
Increase in scalable templates
2.5x
Faster production time
What we did:
- Conducted a line-by-line audit of Customer.io’s HTML to identify structural issues affecting template performance and scalability.
- Collaborated with the Customer.io team to prioritize fixes and develop an implementation plan for complex email use cases.
- Rebuilt the underlying HTML framework to support dynamic content, flexible customization, and repeatable template production.
- Created a scalable foundation that could be applied across multiple communication workflows.
Impact:
- Enabled the production of more than 200 email templates using the rebuilt HTML structure.
- Made template production 2.5x faster.
- Reduced turnaround time from template development to workflow distribution.
- Expanded the range of customizable features available within Customer.io’s communication templates.


