Waverly Studios, a US-based startup building a youth event management platform for organisations like soccer and hockey clubs, engaged me through Toptal for what was initially scoped as a focused task: integrate Auth0 authentication. What I discovered upon joining was a backend that barely existed.

The previous backend developer had departed, and it was immediately clear why. The codebase was in a poor state - I encountered a stack overflow from a memory leak within days of starting while testing the authentication integration. The frontend developer, also a Toptal resource, had done excellent work - but had been forced to stub out backend interactions because the actual backend couldn't support them. The gap between what the business believed they had and what actually existed was significant.

After presenting my findings to the business leadership team (notably non-technical), the engagement expanded dramatically. What started as introducing Auth0 became rebuilding the backend properly. I implemented CQRS patterns to enable future scalability - knowing that a platform like this might eventually need to break into microservices. The authorisation model was particularly interesting: permissions were relational rather than role-based. A coach could only see youth members in their specific group, requiring authorisation logic tied to data relationships rather than simple role checks.

I integrated the full API stack the platform needed: Stripe for payments, subscriptions, and payment distribution via Connect; SendBird for real-time chat features; SendGrid for transactional messaging around event invitations and notifications; and Auth0 for authentication with my own relational authorisation layer on top.

The engagement ran concurrently with Operational Solutions, requiring careful management of a UK contract alongside a US Toptal engagement. I set a target of sub-1.5 second response times and implemented the domain separation that would allow the platform to scale when needed.