Mountaineering Labs Multi-Store Stock Sync for WooCommerce

Run several WooCommerce stores that sell the same products — for example a domestic and an international site — and keep stock quantities in sync automatically.

How it works

• One site is configured as the hub, the authoritative source of stock levels. The other sites are spokes.
• When stock changes anywhere (a sale, a refund/restock, or a manual edit in wp-admin), the change is picked up via WooCommerce’s stock hooks and sent to the hub.
• The hub updates its own stock atomically (safe under concurrent sales on different sites) and broadcasts the resulting authoritative value to all spokes.
• Products and variations are matched across sites by SKU. Works with both simple and variable products.

Reliable by design

• Outbound messages are written to a local queue (a fast database insert) — customer-facing requests never wait on network calls to other sites.
• A background worker delivers queued messages within seconds and retries with backoff if a peer site is temporarily unreachable. Temporary outages cause delay, not data loss.
• Every message carries a unique id; receivers ignore duplicates, so retries can never double-apply a stock change.

Secure

• Sites communicate over a dedicated REST endpoint authenticated with an HMAC-SHA256 signature over a shared secret — no WooCommerce API keys needed.
• Stale requests are rejected and duplicate message ids are ignored (replay protection).

Languages

English admin UI, fully internationalized. Translations are managed through translate.wordpress.org and delivered automatically.