Challenge

The existing codebase was fragile and insecure, making it difficult to ship new features or onboard new users. The goal was to stabilize the platform and modernize the infrastructure to support aggressive growth targets.

Solution

I engineered a complete overhaul of the system, transitioning from a legacy monolith to a modern architecture:

• Decoupled the system into a high-performance SPA (Single Page Application) frontend and a secure RESTful API.
• Audited and patched critical vulnerabilities, implementing industry-standard authentication and data protection protocols.
• Refactored "messy" legacy code into clean, maintainable, and documented modules.

Result

The technical modernization allowed Zenfit to onboard significantly more customers, resulting in a 3x increase in the user base. The increased stability and scalability of the platform were key factors in Zenfit’s eventual acquisition by a major industry player.