What is ATP and why does it matter?

Available-to-promise (ATP) is sellable quantity after reservations, holds, and in-transit commitments. We calculate ATP per location and channel so storefronts never promise units that ops cannot ship — and we keep that number authoritative when WMS, ERP, and commerce disagree.

Can you connect WMS, Shopify, and our ERP?

Yes. We design event-driven sync between WMS receiving, ERP ledger, and commerce channels (Shopify, Magento, and others) so on-hand, allocated, and available quantities stay aligned — with conflict rules, idempotent consumers, and audit trails when systems disagree.

How do you prevent oversells across channels?

Shared inventory pools, channel buffers, soft locks at checkout, and hard commits on payment. Omnichannel availability exposes only what is safe to sell after safety stock and transfer lead times — even when multiple channels reserve the same SKU in the same second.

Do you support multi-warehouse and 3PL networks?

We model nodes, bins, and transfer orders across owned DCs, retail backrooms, and 3PLs — with routing rules for nearest-node fulfillment, split shipments, and allocation that respects SLA and cost.

How does safety stock forecasting work?

Demand signals, lead-time variability, and service-level targets feed reorder points and min/max policies. Planners see projected stockouts before promotions or seasonality hit the floor — with SKU-node granularity, not a single global buffer.

What about barcode scanning and receiving?

Mobile receiving, putaway, and cycle-count flows with barcode/QR validation, ASN matching, and exception queues so warehouse reality updates inventory before the next sales wave.

Will we own the inventory platform?

You own the repositories, cloud resources, and integrations we provision. We document SKU models, sync maps, and runbooks so your ops and engineering teams can extend the system.

How long does an inventory build take?

A focused Shopify + ERP sync with single-warehouse ATP can ship in 6–10 weeks. Multi-node WMS, forecasting, and omnichannel pools typically run 12–20 weeks for the first production release.

What does Zupitrix own technically on inventory projects?

Availability model design, reservation and allocation services, WMS/ERP/commerce event pipelines, oversell guards, observability for ATP drift and exceptions, load testing of reserve → commit under peak, and documented handoff. Warehouse process change management stays with your ops leads — we build the systems that make floor counts match the storefront.

How do you keep WMS, ERP, and Shopify from disagreeing?

One authoritative ATP core. WMS and ERP publish events; commerce only consumes publish feeds. Conflict rules, version stamps, and audit trails resolve disagreements — we never let three systems each invent sellable quantity independently.

Warehouse ops · ATP · channel sync

Stock that matches
the floor and the storefront.

Zupitrix builds inventory management and WMS-connected systems with real-time ATP, multi-warehouse truth, Shopify/ERP sync, and safety-stock rules that stop oversells before they hit checkout — so ops, finance, and channels share one sellable quantity.

Start Project View Portfolio

ATP & WMS
Multi-warehouse
Shopify / ERP sync
Oversell prevention

Warehouse aisle with pallet racking and stock control

16,947On hand

14,058ATP

2,218Reserved

12Nodes live

Network

Multi-warehouse reality, one ATP story

DCs, 3PLs, backrooms, and dark stores share a single availability model — so omnichannel channels sell what each node can actually ship, with allocation that respects SLA, cost, and safety stock.

DC-EASTHealthy

East coast DC

Primary fulfillment with bin-level accuracy, wave picking, and ATP that updates as soon as putaway closes.

62k SKUs

3PL-NWSyncing

Northwest 3PL

ASN receiving and SLA-backed ship confirmations that feed the same availability model as owned DCs.

18k SKUs

STORE-04Live

Flagship backroom

BOPIS and ship-from-store with soft locks at POS and web so floor stock is never double-sold.

4.2k SKUs

DARK-02Peak ready

Urban dark store

Same-day radius inventory with tighter safety buffers and faster reservation timeouts.

1.1k SKUs

How Zupitrix solves it

Technical path from node chaos to one sellable ATP

Multi-warehouse oversells are an engineering problem: competing sources of truth, laggy 3PL feeds, and channel publishes that race each other. Here is how we wire the network so every node stays honest under load.

One SKU-node ATP ledger

Every DC, 3PL, backroom, and dark store writes to the same on-hand / allocated / reserved / safety-stock model — so checkout never invents a second inventory number.

PostgreSQL · audit ledger

Node-aware event ingest

ASN receives, putaway closes, pick confirms, and 3PL feeds land as idempotent events with location keys — ghost stock cannot enter ATP from a lagged CSV.

Kafka · version stamps

Allocation that respects SLA

Orders route to the best live node by ship promise, cost-to-serve, and buffer rules — BOPIS soft-locks store stock while DCs keep wave capacity for ship-from-warehouse.

Rules engine · Redis locks

Channel publish without drift

Shopify, marketplaces, and POS consume one ATP feed with per-channel buffers. Soft lock at cart, hard commit on payment — two nodes cannot sell the same unit under peak.

Webhooks · TTL reservations

Floor truth

Aisle-level SKU accuracy

Bin locations, holds, and transfers stay tied to sellable quantity — not a spreadsheet that drifts after every promo.

Warehouse shelving packed with inventory

A-12SKU-88421

Bin accuracy

Cycle counts and directed putaway keep location truth tied to sellable ATP — not a nightly batch that drifts.

99.8% accuracy

B-03SKU-22019

Variant matrices

Size/color and lot/serial tracking without exploding channel catalogs or losing ATP per variant.

99.4% accuracy

C-07SKU-44102

Hold & quarantine

Quality holds remove units from ATP instantly across every channel the moment QA flags them.

100% accuracy

D-01SKU-91033

Transfer visibility

In-transit stock is promised only after lead-time and receive windows — never while it is still on the truck.

99.1% accuracy

How Zupitrix solves it

Technical path from aisle drift to trusted ATP

Floor truth fails when bins, variants, holds, and transfers live outside the sellable ledger. Here is how we wire aisle-level accuracy so channel ATP matches what is actually on the shelf.

Location-bound stock records

Every unit lives on a bin/aisle key in the ledger. Cycle counts and putaway close against that key so ATP moves with the pallet — not a warehouse-wide guess after promo spikes.

Bin IDs · directed putaway

Variant & lot ATP without catalog blow-up

Size/color and lot/serial sit as inventory dimensions under one parent SKU. Channels publish the right sellable matrix while WMS keeps lot quarantine out of ATP.

SKU matrix · lot/serial

Instant hold propagation

QA and damage holds flip a status flag that zeros channel ATP in the same event path as receiving — no waiting for a nightly feed to pull bad units off the PDP.

Hold events · channel revoke

In-transit that cannot oversell

Transfer stock is tagged in-transit with lead-time windows. Promise logic only unlocks sellable qty after the receive scan — never while inventory is still on the truck.

Transfer states · receive gates

Receiving

Scanning that updates stock before the next sale

01

ASN match

Scan inbound against expected receipts; flag short/over before putaway so ghost units never enter ATP.

02

Putaway

Directed locations update on-hand and free ATP for the right node the moment the bin scan closes.

03

Cycle count

Blind or guided counts reconcile variances with audit trails ops and finance can both trust.

04

Ship confirm

Pick/pack scans decrement allocated stock and release channel holds without waiting for a nightly job.

How Zupitrix solves it

Technical path from dock scan to live ATP

Receiving fails when scans are offline paperwork. We wire ASN match, putaway, cycle count, and ship confirm as ledger events so stock is honest before the next cart locks a unit.

ASN as a contract, not a suggestion

Inbound scans validate against expected lines and quantities before putaway. Shorts, overs, and unknown SKUs land in exception queues — ghost units never open ATP.

ASN APIs · exception queues

Scan-close events update the ledger live

Putaway and ship-confirm scans emit idempotent events with bin and shipment keys. On-hand and allocated qty move in the same path checkout reads — no nightly batch lag.

Barcode events · Kafka

Cycle counts with audit-grade variance

Blind or guided counts write adjustments with who/when/why. Finance and ops share one variance trail; channel ATP only moves after the count posts, not mid-aisle.

Count APIs · audit ledger

Pick/pack that releases holds immediately

Ship confirm decrements allocation and clears soft locks so channels free capacity for the next order in seconds — not after an ERP overnight close.

Ship confirm · lock release

Integrations

ERP and channel sync that stops ghost stock

Event-driven maps between WMS, ERP, Shopify, and marketplaces — with conflict rules when systems disagree, so oversell prevention holds under peak load.

Operations dashboard showing system sync metrics

Inventory coreATP · pools · buffers

WMSReceiving · bins · picks
ERPLedger · cost · POs
ShopifyChannel ATP · orders
MarketplacesBuffers · feeds

Planning

Forecasting and safety stock that protect fill rate

Demand signal

Orders, velocity, and promo calendars feed short-horizon forecasts per SKU-node — not a single warehouse average.

+18%Peak week vs baseline

Safety stock

Service-level targets and lead-time variance set buffers that protect omnichannel availability without overbuying.

95%Fill-rate target

Reorder points

Min/max and PO suggestions surface before stockouts — not after the PDP goes gray and ads keep spending.

4.2dAvg lead-time cover

Ops

Fulfillment pipeline and ops dashboard

From reservation to reconcile — inventory moves with the order, and exceptions surface before customers notice.

01

Reserve

Soft lock ATP at cart or payment intent.

02

Allocate

Route to the best node by SLA and cost.

03

Pick

Wave or order-based tasks with scan confirmation.

04

Pack

Cartonization and label print tied to the shipment.

05

Ship

Carrier handoff releases inventory and updates channels.

06

Reconcile

Returns and adjustments close the loop in ERP.

Outbound packages staged for warehouse fulfillment

Ops controlLive

Inventory operations analytics dashboard

14Open exceptions
2,410Units reserved
8/8Channels green
23Stockout risk SKUs

Stack & tooling

Technologies Zupitrix uses for inventory

Commerce platforms, data stores, messaging, search, and typed services that keep ATP honest from bin scan to channel publish.

Commerce

Shopify

Channel inventory, location ATP, and order reservations wired into a shared availability core.

Commerce

Magento

Enterprise catalog and multi-source inventory sync with conflict-safe stock updates.

Data

PostgreSQL

Transactional stock ledgers, reservations, and audit history for every ATP change.

Cache

Redis

Sub-second reservation locks and channel ATP caches under peak checkout load.

Messaging

Apache Kafka

Event streams for WMS receiving, ERP adjustments, and channel stock publishes.

Ops

Docker

Reproducible workers for sync jobs, scanners, and allocation services.

Cloud

AWS

Scalable compute, queues, and storage for multi-node inventory workloads.

Search/ATP

Elasticsearch

Fast SKU-node lookup, exception search, and ATP queries across large catalogs.

Services

Node.js

Reservation, allocation, and sync workers with idempotent handlers and typed stock events.

Language

TypeScript

Typed SKU-node models, reservation state machines, and API contracts ops and commerce share.

API

GraphQL

Precise ATP and allocation queries for storefronts and ops UIs without over-fetching stock payloads.

Technical perspective

How Zupitrix engineers inventory truth

We do not bolt a sync job onto three systems and hope. Zupitrix designs an availability core, wires WMS and ERP as event producers, publishes ATP to commerce channels, and hardens reservation locks for sale day — with audit trails when anything disagrees.

01

Availability & ATP core

A single sellable quantity model per SKU-node-channel — on-hand, allocated, reserved, in-transit, and safety stock — with soft locks at cart and hard commits on payment so two channels cannot spend the same unit.

PostgreSQL
Redis locks
ATP rules
Audit ledger

02

WMS & warehouse events

Receiving, putaway, pick, pack, and ship confirmations stream into the core. Scan validation and ASN matching update truth before the next sales wave — not in a nightly CSV.

Kafka / queues
Barcode APIs
ASN match
Exception queues

03

Commerce & channel publish

Shopify, Magento, marketplaces, and POS consume the same ATP feed. Channel buffers and publish cadence keep storefronts honest under flash traffic without hammering the warehouse system of record.

Shopify
Magento
Webhooks
Elasticsearch

04

ERP reconciliation & ops

Adjustments, returns, and cycle counts close the loop with ERP. Dashboards surface ghost stock, open exceptions, and stockout risk so planners act before customers see a broken promise.

ERP sync
Forecasting
Ops UI
AWS / Docker

Where we add leverage

Technical ways Zupitrix supports your inventory stack

From SKU-node modeling to sale-day reservation load tests — concrete engineering ownership so ops, finance, and channels share one sellable number.

Inventory model designed before integrations

We define SKU, location, lot/serial, and channel pools first — then map WMS and ERP fields to that model so sync does not invent a fourth source of truth.

Reservation protocol that survives peak checkout

Redis-backed soft locks, TTL expiry, and payment-commit paths stop race conditions when two carts hit the same SKU in the same second.

Idempotent event consumers

WMS and ERP events carry keys and version stamps. Retries never double-allocate; out-of-order messages reconcile with clear conflict rules.

Oversell prevention as product logic

Safety stock, channel buffers, and lead-time offsets are configuration — not one-off scripts — so promotions and new marketplaces inherit the same guards.

Observability for ops, not just uptime

Exception queues, ATP drift alerts, sync lag, and stockout forecasts land where warehouse and merchandising teams already work.

Runbooks and ownership handoff

You keep repos, cloud, and admin. We document sync maps, failure modes, and day-two playbooks so Zupitrix is a partner — not the only person who understands the ledger.

Integration map

Wired as producers and consumers — not a nightly CSV

Zupitrix sequences WMS, ERP, commerce, marketplaces, 3PL, and POS before UI polish. Each connection has an owner, a contract, and a failure mode — so Black Friday is a traffic problem, not a surprise sync problem.

WMSProduces
Receiving, putaway, pick/pack/ship confirms, cycle countsEvents → core
ERPReconciles
On-hand ledger, adjustments, returns, financial closeLedger ↔ core
CommerceConsumes
Shopify, Magento, custom storefront ATP & reservationsATP → channels
MarketplacesConsumes
Amazon, Flipkart, and others with channel buffersBuffered publish
3PL / carriersProduces
ASN, inventory feeds, ship manifests, SLA routingASN → core
POS / retailBoth
Store backroom stock and BOPIS allocation rulesLocks ↔ ATP

Zupitrix role

Your technical inventory partner — from ATP model to sale-day sync

Zupitrix engineers the full inventory stack: availability core, WMS event pipelines, channel publish, ERP reconciliation, and the locks that prevent oversells. We own architecture, implementation, load-tested reservation paths, and ops handoff — so floor counts and storefront ATP stay the same number under peak load.

Architecture: ATP core ↔ WMS events ↔ commerce publish ↔ ERP close
Implementation: typed stock services, Kafka consumers, Redis reservation locks
Reliability: idempotent sync, conflict rules, sale-day load tests on reserve → commit
Ops readiness: exception dashboards, forecasting hooks, and documented runbooks
Ownership: you keep code, cloud, and integrations — we leave a map your team can run

Warehouse operations and inventory systems engineering review

FAQ

Questions about inventory management

Keep exploring

Stock that matchesthe floor and the storefront.

Multi-warehouse reality, one ATP story

East coast DC

Northwest 3PL

Flagship backroom

Urban dark store

One SKU-node ATP ledger

Node-aware event ingest

Allocation that respects SLA

Channel publish without drift

Bin accuracy

Variant matrices

Hold & quarantine

Transfer visibility

Location-bound stock records

Variant & lot ATP without catalog blow-up

Instant hold propagation

In-transit that cannot oversell

ASN match

Putaway

Cycle count

Ship confirm

ASN as a contract, not a suggestion

Scan-close events update the ledger live

Cycle counts with audit-grade variance

Pick/pack that releases holds immediately

Demand signal

Safety stock

Reorder points

Reserve

Allocate

Pick

Pack

Ship

Reconcile

Availability & ATP core

WMS & warehouse events

Commerce & channel publish

ERP reconciliation & ops

Inventory model designed before integrations

Reservation protocol that survives peak checkout

Idempotent event consumers

Oversell prevention as product logic

Observability for ops, not just uptime

Runbooks and ownership handoff

Wired as producers and consumers — not a nightly CSV

Your technical inventory partner — from ATP model to sale-day sync

01What is ATP and why does it matter?

02Can you connect WMS, Shopify, and our ERP?

03How do you prevent oversells across channels?

04Do you support multi-warehouse and 3PL networks?

05How does safety stock forecasting work?

06What about barcode scanning and receiving?

07Will we own the inventory platform?

08How long does an inventory build take?

09What does Zupitrix own technically on inventory projects?

10How do you keep WMS, ERP, and Shopify from disagreeing?

B2B Marketplace

B2C Store Development

Payment Integration

Get In Touch

Start project.We'd love to help.

Stock that matches
the floor and the storefront.

Start project.
We'd love to help.