When a booking fails, you need to know which supplier, which call and why — in minutes. Correlation IDs, safe request logging, per-supplier metrics, tracing and alerting that make multi-supplier travel platforms debuggable.
Supplier currency, selling currency and settlement currency are rarely the same. How to store money correctly, snapshot exchange rates, apply markup and rounding, handle refunds and keep FX exposure visible in a travel platform.
Caching makes flight search fast and affordable, but stale fares erode trust and conversion. Strategies for cache keys, TTLs, pre-warming and re-pricing that balance speed, cost and accuracy.
Webhooks look simple until a partner misses an event. How to design webhook delivery with outbox patterns, retries with backoff, signatures, ordering, replay and monitoring that partners can trust.
Microservices solve organisational and scaling problems, but they add distributed-systems complexity. Why a well-structured modular monolith is often the better starting point, and the signals that justify splitting services out.
Search, pricing, booking, payment, ticketing and servicing: how the parts of a modern travel booking engine fit together, where they fail, and which design decisions are hardest to reverse.
