Kitgenix Stock Sync for WooCommerce

Kitgenix Stock Sync for WooCommerce synchronizes inventory between WooCommerce stores using a Master/Child architecture. The Master store acts as the authoritative inventory source while Child stores send stock-changing events back to the Master and receive the resulting authoritative stock state. The plugin is built for merchants who sell the same physical inventory through several WooCommerce storefronts and need stock quantity, stock status and backorder behaviour to converge without manually exporting/importing inventory files. Stores communicate directly over signed REST requests; there is no Kitgenix cloud stock relay. Background delivery uses WooCommerce Action Scheduler where available, with retries and backlog handling for temporary failures. Learn more about Kitgenix at Kitgenix. WooCommerce Stock Sync Features

• One authoritative Master store with one or more Child stores.
• SKU-based product/variation matching plus plugin global IDs for stable identity.
• Synchronization of stock quantity.
• Synchronization of stock status.
• Synchronization of backorder setting.
• Synchronization of low-stock amount.
• Effective stock-management mode handling, including variation inheritance from a parent product.
• Automatic capture of WooCommerce stock-change hooks.
• Order-processing and stock-restoration handling.
• Asynchronous event delivery with retries/backoff.
• Per-event version numbers to reject stale updates.
• Duplicate-event detection.
• Persistent backlog for recoverable failed deliveries.
• Conflict scanning and reconciliation tools.
• Strict Child-store checkout validation option.
• Cached stock snapshot/failure strategy options for Master reachability problems.
• SKU rename tracking.
• Product/SKU exclusions.
• Shared-secret rotation with overlap window.
• Signed REST authentication and replay protection.
• Scheduled health checks and connection status.
• WordPress Site Health integration.
• Event log and diagnostic code reference.
• WP-CLI status, audit/reconcile, SKU and backlog tooling.
• WooCommerce HPOS compatibility handling.

Master and Child Architecture The Master owns the authoritative stock state. A Child store can detect a local event that changes stock, send that event to the Master, and then receive the authoritative result that should be applied across the network. This avoids a simple "last store to save wins" design in which two storefronts can continually overwrite one another with stale quantities. The Master configuration stores the connected Child sites and the Child configuration stores the Master endpoint/credentials needed for signed communication. Inventory Fields Synchronized The state payload includes the stock-related fields needed to keep WooCommerce availability consistent, including quantity, status, backorders, low-stock amount and effective manage-stock state. Variable products/variations are handled with awareness that a variation may manage its own stock or inherit stock management from the parent product. The plugin focuses on stock. It is not a general product-catalogue synchronizer for descriptions, images, categories and full pricing; Kitgenix MultiStore Sync is a separate broader plugin for that use case. Automatic Capture of Stock Changes The sync engine hooks into WooCommerce product/variation stock updates, stock-status updates, updated product properties, order processing and stock restoration. This means stock changes made by normal WooCommerce operations can enter the sync pipeline without staff having to click a separate "export stock" button. Because third-party integrations such as POS or marketplace connectors often write stock through WooCommerce's normal APIs/hooks, their resulting WooCommerce stock changes can also be observed without the Kitgenix plugin calling the third party directly. Event Versioning and Duplicate Protection Each synchronized product carries plugin metadata used for global identity and event versioning. The receiver tracks the applied version so an older delayed event can be rejected instead of rolling stock backwards after a newer update has already been applied. Event IDs are also remembered for a limited period so a duplicated/retried delivery is not applied as though it were a brand-new inventory movement. Retry and Backlog Handling Outbound failures are classified and retried using increasing delays. Recoverable failures can be persisted in a capped backlog so administrators can see that inventory delivery is pending rather than assuming a silent request succeeded. Backlog entries can be retried or discarded from the administrative tools when appropriate. Successful later delivery removes the corresponding outstanding item. Reconciliation and Conflict Detection The Master can scan Child stores and compare their current stock state with the authoritative record. Reconciliation processes products in batches and can continue through Action Scheduler rather than requiring a single long-running browser request. Conflict reports can identify mismatched stock or duplicate-SKU conditions that need manual attention. The plugin also exposes audit/reconciliation functionality through WP-CLI. Strict Checkout Validation A Child store can optionally validate cart quantities against the Master during checkout. This is intended to reduce overselling when the local storefront's last synchronized value is older than the authoritative stock. Because the Master can be temporarily unreachable, the plugin includes configurable behaviour around failure and stale cached stock snapshots. Stores should choose a strategy that matches whether they prefer checkout availability or strict oversell prevention during network outages. SKU Rename Handling The plugin observes SKU metadata changes so identity can remain consistent when a product's SKU is edited. Global plugin IDs provide another stable identifier used by the sync process, reducing dependence on the assumption that a SKU can never change. Exclusions Administrators can exclude specific SKUs from stock synchronization. Excluded products are ignored by normal event delivery and reconciliation so local-only inventory is not continually overwritten. Secure Signed REST Requests Master and Child REST requests are signed using the shared-secret authentication layer. Requests include timing/identity information and are rejected when they are invalid, too large, outside the accepted window or fail replay/authentication checks. The security layer also contains throttling/temporary lockout behaviour for repeated authentication failures and remote URL validation. Shared secrets can be rotated with a configured overlap period so a network can move from an old secret to a new one without requiring every in-flight request to fail at the exact rotation second. Health Monitoring Scheduled health pings update the stored connection status for the Master/Child relationship. The admin interface and Site Health integration can report configuration, connectivity, backlog and Action Scheduler concerns. WP-CLI The command base is: wp kitgenix-stock-sync The command class includes status, audit/reconciliation, SKU-level actions, backlog/conflict tooling and formatting helpers for operational use from the command line. Direct Store-to-Store Data Flow Stock events and stock-state queries are sent only between the WooCommerce sites configured by the administrator. Kitgenix does not receive the store's inventory feed or act as a remote source of truth. The shared Kitgenix admin Hub can separately request public plugin metadata from WordPress.org, and the admin stylesheet imports Google Fonts as documented in External Services. Those requests do not contain WooCommerce stock payloads. Typical Uses

• Separate retail and wholesale WooCommerce stores sharing one warehouse quantity.
• UK and Ireland storefronts selling from the same physical stock pool.
• Brand/domain-specific stores that must not oversell shared inventory.
• A POS/integration updating the Master while web storefronts follow the authoritative result.
• Stores that need backorder and stock-status behaviour kept consistent as well as the numeric quantity.

1. Install via Plugins → Add New and search for "Kitgenix Stock Sync for WooCommerce", or upload the ZIP to /wp-content/plugins/.
2. Activate the plugin (WooCommerce required – the plugin will deactivate itself if WooCommerce isn't active).
3. Open the settings under the Kitgenix hub (Kitgenix → Stock Sync).
4. Decide which store is the Master and which are Children, then configure the connection on each: Master/Child URLs must use HTTPS, plus a Store ID and a shared secret.
5. Use Test Connection to confirm each pairing before relying on it.
6. Run a Reconcile on the Master to establish stable GIDs and push the current stock state to every Child.
7. Optional: enable Strict checkout validation on Child stores and choose a failure strategy.
8. Optional: server administrators can also drive setup checks and operations via WP-CLI (wp kitgenix-stock-sync status) – see the developer reference below.

The plugin cannot sync anything until at least one Master and one Child are configured and connected – there is no default or automatic pairing.

2.0.0 (31 August 2026)

• New: Redesigned the entire admin settings screen around the shared Kitgenix design system – card-based sections, stat tiles, status badges, and toggle switches replace the old WordPress form tables and status tables.
• New: Added a sticky topbar with the Kitgenix brand, plugin name/version, tab navigation, a link to the Kitgenix Hub, and a mobile hamburger menu, replacing the previous nav-tab bar and static page header.
• New: Added an in-page settings search (topbar search panel with "/" and Cmd/Ctrl+K shortcuts) that filters cards and rows on the active tab as you type.
• New: Added a light/dark theme toggle for the admin UI; the chosen theme is remembered in the browser.
• New: Editing or removing a Child store on the Stores tab now opens an accessible modal dialog instead of an inline form and a JavaScript confirm() prompt.
• New: Event Log and Backlog tables on the Logs tab now support live search/filtering, colour-coded status badges, and empty-state messaging.
• New: Event Log and Backlog tables are now paginated (25 rows per page) so a busy store's history doesn't turn into one long scroll.
• New: Added a diagnostic code reference table to the Logs tab explaining what each recorded category means and whether it needs action.
• New: Added versioned stock state. Every authoritative item now carries a monotonically increasing per-product version; a receiving store records the last version it applied and ignores anything arriving with an equal or older version. Delayed, duplicated, retried, and out-of-order events can no longer overwrite already-current stock.
• New: Added an event envelope. Every sync event now has a stable unique ID plus origin store, creation time, delivery-attempt count, and a schema version – carried through retries rather than regenerated per attempt.
• New: Added a Conflict Dashboard tab covering missing products, missing or duplicate SKUs, GID mismatches, quantity/backorder/stock-status mismatches, Child stores being offline, and authentication errors.
• New: Conflict Dashboard results can now be populated by Audit, Reconcile dry-runs/difference checks, and a dedicated duplicate-SKU scan.
• New: Reconcile now supports selected SKUs instead of requiring all products to be processed.
• New: Added Reconcile dry-run mode so differences can be reviewed without changing stock.
• New: Added a push-differences-only mode to Reconcile.
• New: Added Reconcile run summaries showing processed products, detected differences, and pushed updates.
• New: Added Resume and Cancel controls for in-progress Reconcile runs.
• New: Added Backlog v2. Failed push/send attempts now retain their complete payload, stable event ID, status, and next-retry time so queued events can be resent correctly.
• New: Added per-item manual Retry controls to the Backlog.
• New: Added per-item Discard controls with confirmation to the Backlog.
• New: Added a bounded retry policy so deliveries that exhaust their retry budget are marked for manual attention instead of retrying indefinitely.
• New: Added per-store Connection Health tracking, replacing the previous single global set of health fields regardless of how many Child stores were configured.
• New: Connection Health now records last inbound communication, last outbound communication, last successful communication, last error, remote WooCommerce version, remote plugin version, and a derived connection status.
• New: Added a recurring health-check ping to keep per-store connection status current.
• New: Added merchant-configurable strict checkout validation failure strategies – fail open, fail closed, or use a last-known-good stock snapshot with a configurable maximum age.
• New: Added safe shared-secret rotation from the Stores tab, including a configurable overlap window so both sides of a store pairing can be updated without interrupting synchronisation.
• New: Added WP-CLI commands for server administrators: wp kitgenix-stock-sync status, audit, reconcile, sku, backlog, and conflicts.
• New: Added WordPress Site Health Status checks for role/connection configuration, connection health, backlog items requiring attention, and Action Scheduler availability.
• New: Added a non-secret Kitgenix Stock Sync diagnostic section to WordPress Site Health → Info.
• Improved: Authentication rejections between stores – including missing signatures, bad timestamps, clock drift, replayed requests, and invalid signatures – are now recorded in the Event Log, with clock drift and replayed requests flagged as routine rather than genuine security concerns.
• Improved: Sync failures between stores now distinguish temporary network or connection issues from genuine rejections such as bad configuration or hard errors in both the Event Log and the Status tab's health indicator.
• Improved: The Support tab is now three focused cards – a donate card with a collapsible monthly-amount picker, a "what your support funds" summary, and a single "get involved" panel for reviews, plugin links, and community – replacing the previous stack of donate/trust/community cards and sidebar.
• Improved: Audit Children results are now grouped into collapsible per-child cards instead of one long flat list.
• Improved: The Kitgenix Hub page now shares the same topbar and card design system as the plugin settings screens and shows installed/active plugin counts alongside each listing.
• Improved: Added the Image Optimizer plugin to the Kitgenix Hub's plugin list and updated the MultiStore Sync entry to the renamed "MultiStore for WooCommerce" plugin with its new slug and page.
• Improved: Refreshed the Kitgenix brand logo and favicon assets with new primary, dark, white, and black variants, including tagline versions, and updated the admin menu icon.
• Improved: Outbound stock changes are now coalesced per request, so every product touched by a single operation – such as one order's line items – is sent as a single event instead of generating one network request per WooCommerce hook.
• Improved: The Master's real-time push to Child stores now dispatches asynchronously through Action Scheduler instead of blocking the request that triggered the stock change, matching the behaviour already used by bulk tools.
• Improved: The Master no longer echoes an incoming event back to the Child store that sent it, eliminating an unnecessary round trip and preventing integrations such as WooCommerce Square from creating stock-sync feedback loops when driving a Child store's local inventory.
• Improved: Variations that inherit stock management from their parent using WooCommerce's "parent" stock-management mode are now synchronised and applied faithfully instead of being forced into independently managed stock.
• Improved: Strict checkout validation continues to block checkout in every failure strategy when a reachable Master definitively reports that an item is out of stock or has insufficient quantity.
• Fix: The settings sidebar now sticks flush beneath the topbar based on its real measured height instead of a fixed guessed offset, preventing overlap when the topbar wraps to two lines on narrower screens.
• Fix: Number inputs across the settings screens are no longer cramped to a fixed 50px width.
• Fix: Corrected order stock-reduction/restoration handling where the suppression flag was previously being set after WooCommerce had already fired the per-item stock hooks it was intended to suppress.
• Fix: Replaced the previous order-level suppression workaround with request-scoped stock-change coalescing, removing the dependency on WooCommerce hook ordering entirely.
• Security: Verified compatibility with WooCommerce 11.0 failed-order stock restoration. WooCommerce's wc_maybe_increase_stock_levels() now also runs on woocommerce_order_status_failed, guarded by WooCommerce's own stock-reduced flag, and Kitgenix Stock Sync correctly synchronises the resulting WooCommerce stock state without reimplementing order-status arithmetic.
• Security: Request bodies larger than 2MB are now rejected before HMAC verification.
• Security: Malformed JSON requests now return a clean error instead of falling through into further request processing.
• Security: Repeated authentication failures from the same sender now trigger a temporary lockout.
• Security: Authentication failure responses now use a single generic message so callers cannot enumerate configured store pairings.
• Security: Master and Child store URLs must now use HTTPS, with a filtered exception available for local development environments.
• Dev: Added a new shared kitgenix-admin-components.js script providing modals, collapsible cards, copy-to-clipboard controls, live table search, and toast-style save confirmations.
• Dev: Substantially expanded kitgenix-admin-tabs.js to drive the new topbar, mobile menu, dropdowns, and dynamic sticky-offset behaviour.