Fifteen years building and scaling distributed systems, across the industry's move from bare-metal servers and monoliths to cloud-native, Kubernetes and GitOps. I take on the work teams postpone: paying down technical debt, building deployment from nothing, and keeping systems running.
Six shifts the industry has since packaged and sells ready-made. I worked through them before anything was ready-made.
Sixt
Car rental — a regional booking module · 2022 · Front end, in a contractor's team
Situation
Booking is the whole reason anyone opens a rental site. Pick-up point, dates, class of car, then checkout — and most of that happens on a phone.
What was done
Built and optimised the front end of the regional booking module for one market, as part of a contractor's team — search by location, dates and vehicle class, and the responsive integration of the checkout forms.
What was built
Booking search: pick-up and drop-off location, dates, vehicle class
Result list and vehicle selection screens
Checkout forms and their responsive behaviour
Front-end integration with the payment gateway flow
In numbers
Result render and filtering: 2.8 s → 0.6 s — The step between searching and choosing a car
Peak season: held — A rental business takes its year in a few weeks
What changed
Rendering and filtering the result list went from 2.8 seconds to 0.6 — the step between searching and choosing a car — and the module holds through the holiday peak.
Why it was hard
Search and booking UI modules refactored and their reactive state tightened: the result list was re-rendering in full where a single parameter had changed.
Booking is a funnel where every step can lose the customer, and payment is the step that cannot be retried casually. A form that misbehaves on a phone is a booking that goes to a competitor.
A regional module inside a larger platform: the work had to fit conventions set by other teams rather than invent its own.
Evidence
Delivered under contract. The source and the internal measurements stay with the client, and the figure above is theirs rather than a public benchmark.