PRODUCT ENGINEERING / SYSTEMS
TRACKFLOW
Structure for the work behind performance.
01 / THE PROBLEM
A training week, with everything connected.
A training plan needs to stay useful after it is written: a coach publishes a week, athletes follow their sessions, and both need an up-to-date view.
02 / THE APPROACH
How the system fits together.
TrackFlow pairs a React frontend with an Express API and MongoDB persistence. Weekly plans project into athlete day plans and completion states; incremental synchronization refreshes only the changed storage keys.
Coach / athlete → React interface
Same-origin /api → Express
Storage contract → compatibility cache
Canonical model → MongoDB collections
Monotonic syncVersion → incremental refresh
03 / ENGINEERING DECISIONS
Evolve the model without replacing the UI
A compatibility layer preserves the existing tf_* storage contract while projecting writes into a canonical MongoDB data model.
Keep every athlete in the right context
Records and synchronization are scoped by coachId. A published week becomes daily plans and completion states used by the athlete calendar.
CURRENT SCOPE
The previous public deployment is unavailable. This case study describes the implemented planning and synchronization architecture. Authentication hardening and broader regression coverage remain areas for continued improvement.