Challenge
Inventory drifts between the store and the website.
Agnotic approach
An event-driven sync with a single source of truth and reservation logic so stock stays consistent across channels in near real time.
POS Integration
Retail POS Integration Services
We connect your point-of-sale system to eCommerce, inventory, payments, and CRM so stock, sales, and customer data stay in sync across every channel — instead of drifting apart between the store and the web.
EMV / PCI DSSREST & WebhooksOAuth 2.0GS1
Trusted by global innovators
What POS integration actually involves
A modern retailer runs many systems — POS at the till, an eCommerce storefront, an inventory or ERP backend, a payment processor, and a CRM or loyalty platform. POS integration is what makes them behave as one: a sale in-store decrements the same stock the website sells, and a customer is recognized whether they buy online or at the counter.
The hard part is real-time consistency across systems that were never designed to agree. Inventory races between channels, offline registers sync late, and each platform models orders and customers differently. We build an integration layer — APIs, webhooks, and an event backbone — that keeps stock, orders, payments, and customer records synchronized, with reconciliation for the edge cases retail always produces.
Architecture
See how we design POS integration — real-time inventory sync, order and payment flows, and CRM data unified across store and web.
Common failure modes
POS integration pitfalls — and how we handle them
Challenge
Registers go offline and sync late.
Agnotic approach
Offline-tolerant queuing and idempotent replay so delayed transactions reconcile cleanly without double-counting.
Challenge
Each system models orders and customers differently.
Agnotic approach
A canonical order and customer model that each platform maps to, so an order means the same thing everywhere.
Challenge
Payment and sales totals do not reconcile.
Agnotic approach
Automated reconciliation between POS, payment processor, and finance, with an exception queue for mismatches.
POS Integration Capabilities
The exact connectivity surface behind a POS that stays in sync with the whole retail stack.
eCommerce & channel sync
Two-way sync with Shopify, WooCommerce, and headless storefronts so products, prices, and orders match across store and web.
Inventory & ERP integration
Real-time stock, price, and product sync with inventory, WMS, and ERP so a sale anywhere updates one source of truth.
Payments & reconciliation
EMV/PCI-aware payment integration with automated reconciliation between POS, processor, and finance systems.
CRM & loyalty
Unified customer, order-history, and loyalty data so shoppers are recognized and rewarded across every channel.
Where it runs
POS integration workflows we build
Omnichannel inventory
One live stock picture shared across store, web, and marketplaces.
Order orchestration
Buy-online-pickup-in-store, ship-from-store, and endless-aisle order flows.
Unified customer profile
Merge in-store and online purchase history into one CRM record.
Loyalty & promotions
Consistent loyalty points and promotions applied at the till and online.
Sales & finance sync
Automated posting of sales and payments into accounting and BI.
Multi-location rollups
Consolidated inventory and sales reporting across all stores.
POS integration built for real omnichannel retail
POS projects break on inventory races and offline sync, not on a single API call. We plan for both from the start.
5+
Systems connected per typical build
2–3 mo
Typical integration go-live
Real-time
Cross-channel inventory sync
Standards we build against
Retail integration standards
EMVPCI DSSOAuth 2.0WebhooksGS1REST / JSON
Our Process
How we deliver POS integration
Channel mapping, inventory consistency, and reconciliation treated as the real work.
1.
Discovery & system map
We map your POS, eCommerce, inventory/ERP, payments, and CRM, and define the source of truth for each data domain.
Channel-mapped
2.
Sync & event design
We design the API, webhook, and event flows and a canonical order/customer/product model shared across platforms.
Event-driven
3.
Build & test
We validate flows against real edge cases — offline registers, returns, partial stock, and concurrent sales.
Edge-tested
4.
Go-live & monitoring
Cutover with reconciliation dashboards and alerting so inventory and payment mismatches are caught early.
Reconciled
Integration surface
POS integration points — system, method & direction
The systems an integrated POS connects to and how we handle each.
| System | Typical method | Direction | What flows |
|---|---|---|---|
| eCommerce (Shopify / Woo) | REST / Webhooks | Round-trip | Products, prices, orders, and stock across channels. |
| Inventory / ERP | REST / file | Round-trip | Stock levels, products, and purchase orders. |
| Payment processor | SDK / API | Round-trip | Authorizations, captures, refunds, and settlement. |
| CRM / loyalty | REST / Webhooks | Round-trip | Customer profiles, order history, and loyalty points. |
| Accounting / BI | API / batch | Outbound | Sales, payments, and reconciliation data. |
Retail stacks vary widely. We profile your actual platforms and pick the sync method that keeps them consistent.
Why Partner With Us
15-Minute Scoping CallWhy teams trust us with POS integration
Channels that actually stay in sync — not a nightly export that drifts by noon.
Payments-aware
EMV/PCI-conscious payment integration with reconciliation, so money and sales always tie out.
Retail depth
Fluent across POS platforms, eCommerce, and ERP — we know where omnichannel projects actually break.
Real-time focused
Event-driven sync engineered for near real-time consistency, not slow batch exports.
Full-stack fluency
We connect POS to eCommerce, inventory, payments, and CRM as one system, not isolated interfaces.
Our relevant experience
Omnichannel retail that stays consistent
Frequently Asked Questions
A single POS-to-eCommerce inventory sync can land in a few weeks, while a full omnichannel build across POS, inventory/ERP, payments, and CRM typically runs 2–3 months. The timeline depends on how many systems and channels are involved and how much reconciliation and offline handling the business needs.
Ready to make your channels agree?
Send us your POS, eCommerce, and inventory stack. We will return a realistic omnichannel integration plan.
contact@agnotic.com
Partnerships
contact@agnotic.com