Operations · Architecture
Operations
How real UK sellers keep stock consistent across four very different marketplace APIs, without drowning in cron scripts.
Stock sync sounds simple — it isn't. Each marketplace has a different API shape, a different rate limit, and a different failure mode. Amazon uses Feeds API and FBA Inventory API for two different fulfilment channels; eBay uses REST Inventory API for modern listings and Trading API for legacy ones; Temu has a strict 4 req/sec rate limit; TikTok Shop can be sensitive to maintenance windows. A good multi-channel sync architecture should account for these differences.
Goal of this playbook
By the end of this guide you'll understand how to architect stock sync across 4+ marketplaces so that stock normally updates within a defined target window, with recovery logic for marketplace outages.
You’ll need:
30 min
In MaxInvent, the Product table owns the stock number. Every channel (EbayListing, AmazonListing, TemuGoodsId, TiktokProduct) links back via a centralProductId mapping. Availability is computed from the pool minus buffers rather than being manually maintained per channel.
15 min
Amazon SP-API supports two relevant methods: Feeds API (bulk, asynchronous, often better for larger batches) and Listings Items API (single-SKU, synchronous, often better for low-volume or urgent updates). MaxInvent can choose the appropriate path based on the update type.
Pitfall
Don't exceed Amazon's 'Feeds' endpoint hourly limit (typically 100 submissions/hour for most sellers). MaxInvent batches aggressively — under 50 SKUs per feed is wasteful.
15 min
eBay inventory can differ by listing type. Listings created via modern Seller Hub may use the REST Inventory API (/sell/inventory/v1/), while legacy listings can require the Trading API (/ws/api.dll with GetMyeBaySelling). MaxInvent detects listing type and uses the appropriate API path where available.
10 min
Temu enforces roughly 4 req/sec per seller. With a 1,000-SKU catalogue, that creates a practical floor for a full sync cycle. MaxInvent sets Temu cadence to 30 min by default and can push on dispatch as a backstop.
10 min
TikTok Shop's API is straightforward, but sellers should still account for marketplace maintenance windows and transient API failures. MaxInvent schedules syncs with recovery behaviour rather than assuming every push succeeds.
Design-level — built into the platform
Every sync job must be idempotent (running it twice produces the same result). Every job must checkpoint progress (if it crashes at SKU 500 of 1000, the next run resumes at 501, not 1). MaxInvent stores sync state in the isolated per-marketplace database so a crash on Amazon sync doesn't affect Temu sync.
Ongoing
Drift = time between a stock change in the pool and that change landing on the channel. MaxInvent measures drift every time it syncs and plots it per channel. Agree a target window during onboarding and investigate drift that repeatedly exceeds it.
After following every step, you should be able to verify these outcomes:
Because each marketplace only knows about its own listings. Amazon's SP-API can't tell you that eBay just sold a unit — that information has to flow through a central pool. Any architecture that uses one channel as the source of truth will drift against the others.
In practice, 1-2 minutes per channel, limited by rate caps. For Amazon SP-API, 100 feeds/hour means realistically 1 feed every 40 seconds max. For Temu, the 4 req/sec limit caps you at around 2-3 min for a 1,000-SKU sync. Most UK sellers don't need sub-5-min sync — the cost of engineering it outweighs the oversell-prevention benefit.
Use both where available. Webhooks (event-driven push from your platform to the marketplaces) can be faster but may fail. Polling (periodic sync) is slower but can self-heal. A strong architecture is webhook-first with a polling backstop.
Two things. One: your platform should queue stock updates locally and flush them when the API recovers. Two: on other channels, you normally should not pause selling unless the failure affects the shared stock position. MaxInvent is designed to queue and recover updates, but outage handling should always be tested during onboarding.
It should. If SKU BUNDLE-A is made of 2x SKU-1 and 1x SKU-2, then the exposed stock of BUNDLE-A is min(floor(SKU-1/2), SKU-2). MaxInvent recalculates bundle stock on every component change and pushes to channels that list the bundle.
MaxInvent is built for UK multi-channel sellers. One stock pool across Amazon, eBay, Temu, TikTok Shop, Groupon and more — with the UK’s only native Temu courier label integration.
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