Keeping prices, stock and statuses consistent across several platforms

The typical need

As soon as a business sells or operates on more than one channel — several shops, a marketplace alongside its own site, a delivery app alongside a physical shop — the question of data consistency across those channels comes up quickly. A price changed in one place needs to show up elsewhere, an out-of-stock item needs to disappear everywhere, an order placed on one channel needs to be visible in the overall management system. Without synchronisation, each channel lives in its own reality, and the gaps that build up always end up costing money, whether through overselling, price inconsistency, or a missed order.

How I approach this kind of need

I start by identifying a source of truth for each type of data to synchronise: which system is authoritative for stock, which system is authoritative for prices — these two answers aren’t necessarily the same system. From that source, I build the connectors to each target platform, with a sync frequency matched to how critical the data actually is: stock that affects sellable availability deserves tight real time, editorial content can make do with a daily sync.

True real time — an update propagated within seconds — isn’t always necessary or economically justified. I always discuss the actual need before building an architecture more complex than it needs to be: syncing every few minutes is more than enough for many uses, with an architecture that’s far simpler and more robust than a strict real-time system, which brings its own risk of disorder during a load spike or a partial outage.