Tandem

Tandem was built for parents in the skilled trades, who deal with early starts, overtime, and shift changes that land with little notice. Competitive analysis showed scheduling tools and childcare platforms exist separately, but nothing supported shared childcare coordination between families in one place.

Persona research confirmed the recurring pain points in shift-based households: sudden schedule changes, fragmented communication, and very little time to evaluate childcare options when plans break.

I owned guest access, the real-time collaboration layer, and the profile-linked sharing data models behind multi-user coordination.

Guest auth needed a full lifecycle (create, consume, clear) with cookies tuned for cross-origin iframe embedding: HttpOnly, Secure, SameSite=None. The Socket.IO layer uses centralized typed event contracts and room-scoped handlers rather than global broadcast, paired with persist-first messaging: save over HTTP before the WebSocket fanout, so a refresh or a dropped packet never costs state.

Consolidating scheduling and sharing into one flow cut the common scheduling path from roughly 6–7 interactions to 3–4 focused actions, which matters most exactly when a shift changes at short notice.

Shared availability and group status became readable at a glance, removing the need to switch between a separate calendar and chat for the core coordination loop.