Sentry WMS

Overview

Sentry WMS is a free, open-source warehouse execution system for e-commerce fulfillment teams that can run and maintain a self-hosted application. It fits best when an ERP or order platform already owns products, customers, and orders. The trade-off is straightforward: no software charge, but deployment, HTTPS setup, and integration work remain your responsibility.

Key features

Sentry covers receiving, storage, picking, packing, shipping, and counting. Its Pick Walk workflow batches multiple orders and uses a serpentine route, giving warehouse staff a practical way to reduce backtracking during multi-order runs. Batch picking is the emphasis; this is an execution tool rather than a complete commerce suite.

Inventory control goes beyond a simple quantity ledger. Bin-level cycle counts detect variances and route them through administrator approval, while transfers and adjustments retain a reason. Barcode scanning, mobile access, and multi-warehouse support make the feature set relevant to operations with distributed stock or regular count programs.

The connector framework supplies scaffolding for ERP, commerce, and other HTTP API connections. It does not include first-party connectors for NetSuite, QuickBooks, Shopify, or BigCommerce, so teams using those systems should expect to build or commission the integration. Sentry also explicitly relies on another system for orders, products, and customers; it cannot replace an ERP.

The documented architecture combines a React web admin panel, a React Native (Expo) mobile app, a Flask API, and Docker Compose deployment.

Production safeguards include required secrets, an encrypted connector credential vault, a hash-chained audit log, content security policy, and rate limiting. Connector controls add SSRF protection with DNS-rebinding defense, encrypted credentials that are not returned in plaintext through the API, and audit records for credential writes. The API is HTTP-only, so HTTPS requires a reverse proxy in front of it.

Pricing

Sentry WMS: free. The plan is free and open source with self-hosted deployment, and there is no separate trial period. You avoid recurring license fees, but hosting, administration, reverse-proxy configuration, and connector development are operational costs. Bulk CSV or JSON imports are capped at 5,000 records per import, a limit worth planning around for large catalog or location loads.

Version 1.7.0 and later are licensed under Apache License 2.0; earlier tagged releases remain MIT-licensed. That distinction matters when your compliance or redistribution policy depends on the release you deploy.

Platforms

Sentry supports Android, web, API, and self-hosted deployment. The mobile app is documented for Android sideloading, while the browser-based admin panel handles administration. Docker Compose provides the documented deployment path, and the API can connect the warehouse layer to external systems.

Who it's for

Choose Sentry when you have warehouse staff who need receiving-through-shipping execution, batch picking, cycle-count controls, barcode workflows, and multiple warehouses, plus technical capacity to host the stack and connect it to an existing business system. It is especially suitable for organizations that value open-source control and can operate their own infrastructure.

Look elsewhere if you need a standalone system for orders, products, and customers, or if your team expects ready-made commerce and ERP integrations. The absence of first-party connectors and the required reverse proxy make it a poor fit for businesses seeking a turnkey cloud rollout.

Pros and cons

Pros

• No license fee: the free, open-source plan removes per-seat software pricing and supports self-hosting.
• Focused warehouse execution: receiving, storage, batch picking, packing, shipping, and counting are covered in one operational layer.
• Useful inventory governance: variance detection, approval workflows, and reason-tracked adjustments improve accountability during counts and corrections.
• Security-conscious connectors: encrypted credentials, SSRF and DNS-rebinding defenses, and audit logging address common integration risks.

Cons

• Not an ERP: another system must manage orders, products, and customers.
• Integration work is yours: the framework is scaffolding, with no first-party NetSuite, QuickBooks, Shopify, or BigCommerce connectors.
• Self-hosting demands infrastructure skills: Android sideloading, production secrets, Docker Compose, and a reverse proxy for HTTPS add deployment overhead.
• Import ceiling: each bulk CSV or JSON import can contain at most 5,000 records.

Alternatives

For a broader directory of fulfillment tools, see Order Fulfillment Software, or compare warehouse-focused products in Warehouse Management Software.

• OpenBoxes is worth choosing when you want a freemium warehouse system with Android, iOS, web, API, and self-hosted options, including a free community plan with unlimited users.
• ShipBob suits teams already using ShipBob that want its free customer software for ecommerce stores, inventory, orders, and shipments.
• Vinculum Vin OMS is an alternative for buyers prepared to request a demo and discuss custom pricing.
• Cin7 Omni is a paid option with web, iOS, and Android access, including a plan with eight users, five ecommerce/app integrations, and unlimited inventory locations.
• Descartes Sellercloud is a paid platform with Android, iOS, web, and API access and annual subscription pricing based on order volume and add-ons.
• fulfillmenttools is an enterprise platform with a free trial and demo-led pricing.
• Orders Now is another free option delivered through the Orders Now service.

Verdict

Sentry WMS is a strong choice for technically capable e-commerce operators that need open-source, multi-warehouse execution without a software license bill. Its main reason to choose it is the combination of batch picking, controlled cycle counts, barcode support, and self-hosted control. Look elsewhere if you need an ERP replacement, turnkey connectors, or managed deployment; those requirements turn its low price into a larger implementation project.