Case study · Not documented
Online Stone Solutions
When shipping depends on more than destination and weight, Shopify's standard rate table quickly runs out of vocabulary.
- Shopify
- Custom Shopify App
- Node.js
- Shopify APIs
- Discipline
- Custom shipping logic · Shopify app · Rate calculation
- Year
- Not documented
- Engagement
- Fixed scope
- Status
- Live
01Context
- Implement custom shipping/rate calculations.
- Integrate calculated results with Shopify.
- Keep complex business rules maintainable outside the theme.
Online Stone Solutions sells products where shipping calculations require more specific business logic than ordinary flat rates or carrier defaults.
The shipping experience needed custom calculation behavior tied directly into Shopify.
HeapByte developed application-level logic to calculate and expose rates according to the store's requirements.
02What was in the way
- 01
Non-standard rate rules
The store's shipping logic could not be represented accurately by basic Shopify settings.
- 02
Checkout integration
Calculated values must arrive at the correct point in the purchase flow.
- 03
Maintainability
Shipping rules are operational logic and need to remain understandable when business conditions change.
03Architecture
What we built, and what we deliberately left alone.
- 01
Custom calculation engine
Shipping decisions are computed in application code.
- 02
Shopify integration
Calculated results connect back into Shopify's commerce flow.
- 03
Rule separation
Business logic remains separate from storefront presentation.
Delivery
- Shipping-rule discovery
- Calculation engine
- Shopify integration
- Edge-case testing
- Production rollout
04Outcome
- Rate logic
- Custom
- Theme dependency
- Reduced
- Checkout workflow
- Integrated
Business-specific shipping calculation implemented
Core shipping rules moved into application logic
Custom rates participate in Shopify purchasing
05Engineering notes
- Rule engine
- Shipping factors are evaluated through custom application rules.
- API integration
- The service exchanges relevant cart/order context with Shopify.
- Checkout handoff
- Calculated shipping information is surfaced at the appropriate Shopify stage.
- Error handling
- Fallback behavior prevents unusual input from silently producing invalid rates.
What we took from it
- 01Shipping calculations belong in a testable business-logic layer.
- 02Checkout-facing logic needs aggressive edge-case testing.
- 03Storefront JavaScript is not an appropriate source of truth for shipping rules.
- 04Custom rate engines are easier to evolve when inputs and formulas are explicit.
Disciplines applied
Next case study
Culture Goods
We connected Shopify pricing logic with Google Sheets, creating a custom calculation workflow that lets business-managed data drive ecommerce behavior.
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