Shopify Custom API Development

Complex B2B pricing logic, proprietary back-office systems, and custom checkout rules regularly fall outside what a certified connector or Shopify app can handle. Shero builds against Shopify's Admin API, Storefront API, Webhooks, and Shopify Functions for clients whose business logic requires a purpose-built solution.

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Logo STX
Painful Pleasures Logo
Archer Roose Logo
Sarris Candies Logo
Shopify Premier Partner

16+

Years in business

500+

Projects Delivered

50+

Team Members

98%

Client Retention

40+

custom API integrations delivered

For B2B manufacturers, hybrid operations, and DTC brands where business logic required a purpose-built integration

16+

years on Shopify Plus

Custom integrations built through every major Shopify API version including the migration from REST to GraphQL

June 2026

Shopify Scripts retire

Scripts stop executing June 30, 2026. All custom checkout logic must be in Shopify Functions. Shero migrates existing Scripts and builds new Functions.

98%

client retention post-launch

Most Shero clients continue working with the team after launch on support, development, and marketing programs

"I wanted to thank you all for a very successful launch. Our accounting and sales teams are thrilled to have this functionality working, and our customers are taking full advantage of these enhancements. We appreciate the partnership and look forward to more."

Bren Rafaelly, Head of Digital Transformation, Benchmade

Custom Shopify API development: when to build instead of configure

Custom API development is the right approach when no app covers the requirement, when a connected system has a non-standard data model, or when checkout logic needs to run inside Shopify using Functions. Shero builds against the Admin API for back-office data, Storefront API for headless requirements, Shopify Functions for checkout and discount logic, and Webhooks for event-driven automation.

  • Shopify Admin API
  • Shopify Storefront API
  • Shopify Functions (checkout, discounts, shipping)
  • Webhooks and event-driven flows
  • Private and custom app development
  • API version management and maintenance

Why complex Shopify operations work with Shero on custom API builds

Custom API integrations built without thorough data mapping and error handling create the same problems as bad connector configurations, just harder to diagnose. Shero maps the data model and business logic first, then writes the code.

01

API surface selected based on the requirement, not habit

Shopify has six distinct API surfaces. Shero selects the correct one for each requirement: Admin API for back-office data, Storefront API for frontend and headless, Functions for checkout logic, Webhooks for event-driven automation.

02

Shopify Functions replace Scripts as of June 2026

Shopify Scripts stop executing June 30, 2026. All custom checkout, discount, and shipping logic must move to Functions before that date. Shero migrates existing Scripts and builds new checkout logic in Functions from the start.

03

Business logic documented before development begins

Custom API integrations fail when edge cases surface during development. Shero documents the complete business logic, error conditions, and workflow exceptions before writing any code. This produces an accurate fixed scope.

04

B2B custom logic for pricing, accounts, and checkout

Benchmade and Tormach both required custom API logic for B2B requirements outside Shopify Plus native features: configure-to-order product data, dealer checkout flows, and ERP-sourced pricing. Shero built and maintains these across API version updates.

05

API version management across Shopify's deprecation schedule

Shopify deprecates API versions on a defined schedule. Shero manages version updates for clients on ongoing support arrangements, updating integrations before deprecation affects production.

06

Documentation handed over so your team understands what was built

Shero delivers integrations with endpoint specs, data flow diagrams, error handling runbooks, and version management plans. The documentation is complete enough for an internal team or future agency to maintain.

Our Work

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Well-known American knife manufacturer

Benchmade

For more than three decades, Benchmade has been known for producing high-quality knives for everyday carry, hunting, rescue, and outdoor use. Launched on Magento Commerce Cloud in 2018, the brand partnered with Shero to tap into the surge in outdoor consumer demand and scale their online presence.

Benchmade
Sports equipment for lacrosse and field hockey

STX

STX Sporting Goods is a leading global manufacturer of innovative sports equipment and apparel, catering to athletes and enthusiasts in lacrosse, field hockey, and other team sports. Renowned for its cutting-edge technology and premium products, STX sought to revamp its digital presence to align with its reputation for excellence.

STX
Body jewelry and tattoo supplies

Painful Pleasures

Painful Pleasures is a long-standing supplier of body jewelry and tattoo supplies with a catalog of 40,000+ products. The brand partnered with Shero to complete a stalled Magento to Shopify migration and deliver the complex custom features their business depends on.

Painful Pleasures
Finland's leading music instrument retailer

F-Musiikki

F-Musiikki is one of Finland's leading music instrument retailers, serving both consumers and businesses with over 15,000 products. Looking to reduce costs and modernize their platform, the brand partnered with Shero to migrate from Magento to Shopify Plus and launch a hybrid B2C/B2B store in just two months.

F-Musiikki

Custom API integrations scope to 6-16 weeks depending on systems, data complexity, and whether Shopify Functions are included. We scope before we quote.

Scope my custom API build

How Shero builds custom Shopify API integrations

01

Discovery: Business Logic and API Surface Mapping

We document the complete business logic including edge cases, error conditions, and workflow exceptions. We identify the correct Shopify API surface for each requirement and define the data model mapping between Shopify and connected systems.

02

Architecture: Integration Design and Specification

We produce an integration specification covering API endpoints, data flows, field mappings, transformation rules, error handling, and version management. For Shopify Functions, we design the checkout or discount logic before any code is written.

03

Build: Custom Integration Development

We build against the specified API surfaces with field-level validation, error logging, retry logic, and monitoring. For Functions, we build and deploy the extensions. For webhook flows, we build and test event handlers.

04

UAT: Logic Validation and Edge Case Testing

We test every documented scenario including normal flows, error conditions, data edge cases, and concurrent request handling. API rate limit behavior and timeout handling are tested explicitly before go-live.

05

Launch, Documentation, and Maintenance Handoff

Go-live includes endpoint documentation, data flow diagrams, error handling runbooks, and a version management plan aligned to Shopify's API deprecation schedule.

06

Ongoing: API Version and Business Logic Maintenance

Shopify API versions update on a defined schedule. Business logic evolves. Shero manages version updates and logic changes for clients on ongoing support arrangements so integrations stay current without emergency fixes.

Frequently asked questions.

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What our clients say.

We design experiences that make a difference. See what our clients have to say about working with us.

STX

"Since partnering with Shero Commerce, our eCommerce revenue has grown by 200%. Their 24/7 support and innovative solutions have been game-changers for our business."

James McKenna

Senior Commerce & CX Manager / STX

Painful Pleasures

"Our journey from Magento to Shopify was riddled with complexities and challenges. With a vast catalog and intricate B2B logic, we needed expertise that could navigate through these intricacies. Shero Commerce was our beacon. They not only provided innovative solutions but also utilized their vast Magento knowledge to bridge gaps in Shopify’s native features. Now, our platform is seamless, our costs are reduced, and the headaches are a thing of the past. A heartfelt thank you to the Shero team!"

Patrick Rice

CEO / Painful Pleasures

Swag Golf / Strike 2

"We partnered with Shero for the development work on the SWAG site. The dev was highly nuanced, specialized and complex—and the brand demanded a UX that was smooth, straightforward and memorable. The Shero team went above and beyond from the jump. As a partner to us, they were collaborative, organized and professional. As a partner to our client, they consistently set expectations clearly—and usually exceeded them. We were immediately faced with the challenge of getting this site up on a faster timeline than any similar project we’ve done before. Because of Shero’s tight process and expert dev talent, hitting this deadline was a walk in the park. And most importantly they are a group of terrific people and were a delight to work with. I can’t wait for our agencies to partner again."

Matt Kaminsky

Co-founder & Managing Director / Swag Golf / Strike 2

Justrite Safety Group

"The collaboration between us and Shero Commerce on the Justrite multi-store site went beyond what we had hoped for.  They are a terrific partner to work with.  Their team’s dedication to understanding our unique requirements and delivering a high-quality, customized solution has greatly enhanced our online presence. The new website not only showcases our products effectively but also streamlines the shopping experience for our customers. We couldn’t be happier with the results and look forward to working with Shero Commerce on future projects."

Douglas J. Stang

VP of eCommerce / Justrite Safety Group

And you?

Let's build something great together.

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