🛡️ Server-Side Checkout Protection

Un-Bypassable Checkout Rules
That Protect Merchant Margins

Stop shipping errors, sample kit abuse, and PO Box freight penalties before payment completes. Built 100% on native Shopify Functions for sub-5ms edge execution.

Test Interactive Rule Simulator ↓ View Merchant Manual

Live Simulator

See How CartShield Intercepts Invalid Orders

Select a rule scenario below to experience the native Shopify checkout validation response in real time.

Select Validation Scenario:

Execution: cart.checkout.validation (Wasm)

Zero theme code modification required. Evaluates instantly inside Shopify's secure sandbox.

ModStore Official Checkout

🔒 256-Bit SSL

⚠️

Freight Delivery Restriction

Heavy freight items cannot ship to PO Boxes. Please enter a physical street address.

Cart Contents

🏂 Pro Snowboard Freight (Heavy Goods) $729.95

Customer Shipping Address

PO Box 4829, Springfield, OR 97477

Built for Shopify Functions

Essential Protection Features

📦

PO Box & Freight Blocker

Detects PO Box, APO/FPO, and postal variants in shipping addresses to prevent courier freight rejections.

🎁

Sample Abuse Shield

Prevents low-margin samples, warranty add-ons, or gift packaging from checking out without main catalog items.

🏢

B2B Wholesale Steps

Enforces minimum carton quantities and case multiples (packs of 6 or 12) for tagged B2B wholesale buyers.

⚡

Sub-5ms Execution

Compiled to WebAssembly and executed on Shopify's global edge network. Zero external network latency.

Transparent Pricing

Simple Plans That Scale With Your Store

Choose the plan that fits your protection needs. Upgrade or cancel anytime.

Free Starter

Starter Tier

For new stores establishing basic checkout rules

$0 / month

✓ 1 active validation rule
✓ Up to 30 blocked orders per month
✓ PO Box or Add-on protection
✓ Native Shopify Functions execution
✓ Standard email support

Install Free

Pro Growth

Complete Suite

For growing brands seeking comprehensive protection

$19.99 / month (or $190/year)

✓ Unlimited active validation rules
✓ All rule types (PO Box, Add-ons, Spend limits)
✓ B2B Wholesale case multiples
✓ Native Shopify Functions execution
✓ Real-time blocked order analytics
✓ Priority developer support

Start 14-Day Free Trial

All charges are billed securely via official Shopify Recurring Application Charges. Cancel anytime directly in your Shopify Admin.

Un-Bypassable Checkout Rules That Protect Merchant Margins