Book a Call
Services Work Process Why Us Book a Call →
Shopify Plus Engineering Partner

Shopify commerce,
engineered properly.

We build storefronts, checkout extensions, and Shopify Functions for brands that have outgrown freelancers. No templates. No shortcuts.

No sales pressure. A direct conversation with the engineers who'd build it.

checkout.discount-function.ts
1export function run(input: FunctionInput): FunctionRunResult { 2 // Applies tiered discounts at checkout — evaluated server-side 3 const cart = input.cart; 4 const tier = resolveTier(cart.buyerIdentity); 5 6 if (!tier) return { operations: [] }; 7 8 return { 9 operations: [applyDiscount(cart, tier)] 10 }; 11}

Trusted by ambitious Shopify brands

Gymshark Allbirds MVMT Watches Kylie Cosmetics Beardbrand Chubbies Death Wish Coffee Pura Vida Bulletproof Liquid Death Outer Tushy
0+
Shopify Plus Builds
Storefronts & checkout extensions
0%
Avg. Conversion Lift
Across all CRO engagements
$0M+
GMV Supported
Client revenue on our builds
0%
Client Retention
Long-term engineering partners
What We Do

Shopify engineering, end to end

Every engagement is scoped around one outcome — a storefront that performs, converts, and holds up under real traffic.

Shopify Plus Engineering

Checkout UI extensions, Shopify Functions, B2B storefronts, and multi-store architecture for enterprise merchants.

FunctionsB2BMulti-store

Theme & Storefront Development

Custom Liquid and Hydrogen builds engineered for speed and flexibility — never a bloated third-party theme.

LiquidHydrogenTheme Dev

Checkout & Post-Purchase

Custom checkout extensions, upsells, and payment customizations built directly on Shopify's checkout APIs.

ExtensionsUpsellsPayments

Performance Engineering

Sub-2-second load times. We audit, rebuild, and optimize for Core Web Vitals scores that beat the competition.

Core Web VitalsSpeedSEO

Conversion Engineering

Structured experimentation — funnel instrumentation, hypothesis-driven testing, and disciplined iteration.

A/B TestingAnalyticsFunnels

Subscriptions & Retention

Recurring revenue infrastructure — subscription flows, loyalty systems, and retention mechanics built for LTV.

SubscriptionsLoyaltyLTV
Built on the platform

Deep in Shopify's checkout, not around it

Most agencies stop at the theme layer. We build inside Shopify's checkout extensibility APIs and Functions — the same infrastructure Shopify itself uses for Plus merchants.

  • Custom checkout UI extensions, not workarounds
  • Server-side discount & shipping logic via Shopify Functions
  • B2B pricing, payment terms, and multi-location checkout
checkout.yourstore.com
Subtotal$186.00
ShippingFree
Tier discount (VIP)−$18.60
Total$167.40
Pay now
Secured by Shopify
Featured Work

Results that speak for themselves

We don't just build storefronts — we engineer revenue-generating systems backed by data and disciplined design.

+41% CVR +28% AOV Shopify Plus
Shopify Plus · CRO · Design

Premium Apparel Replatform

Full Shopify Plus migration and redesign for a 7-figure DTC apparel brand. Rebuilt checkout flow and product pages to crush conversion benchmarks.

+63% Subscribers 2.1× LTV Subscriptions
Subscriptions · UX · Retention

Subscription Engine Overhaul

Redesigned the entire subscription experience for a health & wellness brand — from PDP to portal. Subscriber count doubled within 60 days of launch.

1.4s Load Time +22% Revenue Performance
Performance · A/B Testing · Dev

Speed & Conversion Sprint

Complete performance audit and rebuild for a luxury skincare brand. Achieved 1.4s load time and ran 12 successful A/B tests in 90 days.

How We Work

A structured process, built for growth

From day one to scale — a disciplined engagement that delivers results without surprises.

01

Discover

Deep dive into your brand, customers, analytics, and technical stack to define the roadmap.

02

Design

Conversion-first UX wireframes and precise UI design, built in Figma alongside your team.

03

Build

Clean, performant code. Custom Shopify development with thorough QA and staging review.

04

Ship

Launch, measure, and improve. We run experiments continuously until we find what moves the needle.

05

Scale

Ongoing partnership — new features, seasonal campaigns, and infrastructure as your brand grows.

Why Checkout Masters

The engineering partner, not another agency

We don't do everything — we do Shopify exceptionally well. We're brought in after brands have outgrown freelancers and generalist agencies and need engineering that holds up at scale.

Start a Project →

Senior Engineers Only

Every project is staffed by Shopify Plus certified developers — no juniors learning on your codebase.

Fast Execution

We move quickly without sacrificing quality. Most projects launch in 6–10 weeks, not six months.

Direct Access

You work with the engineers building your store — no account managers relaying messages.

Fixed Scope, No Surprises

Clear timelines and deliverables agreed upfront. What we scope is what we ship.

Post-Launch Support

We stay on as long-term partners — monitoring, iterating, and scaling as your brand grows.

Testimonials

What our partners are saying

"
Checkout Masters completely transformed our Shopify store. Our conversion rate jumped 38% within the first month after launch. They think like engineering partners, not vendors.
JM
James Mitchell
Founder — Apex Apparel Co.
"
The team built our entire subscription experience from scratch. We went from 800 to 2,100 active subscribers in 8 weeks. The ROI has been extraordinary.
SK
Sarah Kim
CEO — Vital Wellness
"
I've worked with three Shopify agencies. Checkout Masters is the only one that understood both engineering and performance equally. Our site now scores 94 on PageSpeed.
RN
Ryan Nakamura
Head of Ecommerce — LuxeSkin
Let's Work Together

Ready to build something that holds up?

Book a free 30-minute discovery call. We'll audit your current store, identify your biggest growth opportunities, and outline exactly how we'd approach your project.

No sales pressure. Just a genuine conversation about your brand.