The problem
ItchTix powers ticketing for hundreds of small-venue events. The booking funnel worked beautifully on broadband - and fell apart at the actual venue, where Wi-Fi alternated between awful and absent. 18% of checkouts dropped off on the network screen alone.
The existing booking flow couldn't be patched. It needed to be rebuilt as an offline-tolerant, forgiving web application that talks to the venue's POS directly instead of depending on a perfect connection.
What we built
An internal web application architected around optimistic UI, durable retry queues and a direct POS integration. Staff always see progress, even when the network doesn't agree.
- Optimistic checkout - bookings commit locally, sync when the network comes back, reconcile against server truth.
- Idempotent retry queues with exponential back-off, surfaced to the user only when truly necessary.
- Direct POS integration - bookings and payments sync straight into the venue's point-of-sale system, with no manual re-entry.
- Crash-resilient state persisted locally in the browser so staff pick up exactly where they left off after a refresh or dropout.
How we shipped it
Two-week sprints. Testing on real venue hardware over throttled and intermittent networks. We instrumented every step of the funnel and watched it improve weekly through the build.
What we measured
- Checkout completion rate
- POS sync speed & reliability
- P50 / P95 booking latency
The result
Checkout completion improved 27 percentage points with seamless real-time POS sync. P50 booking latency is 110ms - and network dropouts no longer interrupt venue operations.
Operator's note
"Calm, direct, and obsessively focused on the metric we'd agreed on. The deploy was a non-event - which is the highest praise." - Marcus L., CTO, ItchTix