Shopify engineeringfor brands ready to scale.
We help D2C brands and agency partners turn ambitious ideas into fast, scalable Shopify experiences — from custom development and migrations to integrations, international expansion and CRO implementation.
Engineering-led. Commerce-aware. Built to last.
Shopify Development · Store Builds & Migrations · Apps & Extensions · CRO Implementation · Performance Optimization
Selected brands we have worked with
The Reality Check
Your store can be “working” and still holding your business back.
High-volume merchants often deal with hidden issues that compromise their conversion rates and scalability.
Your store is technically 'working' but your mobile conversion rate tells a different story.
You've outgrown your current Shopify plan but don't know the right path to Basic → Advanced → Plus.
A third-party app, pixel, or poorly written script is quietly destroying your page speed — and you can't tell which one.
You're migrating from Magento and worried about losing SEO rankings, order history, and complex catalog data.
Your CRO team has solid ideas but no technical partner who can build them cleanly into the storefront.
You want to sell across multiple countries but Shopify Markets, multi-currency, and localised content feel complex.
Your development agency writes code that works today but becomes unmaintainable in six months.
That's where CartScaler comes in.
Get Free Store & Plan Consultation →The Engineering Arm for CRO Specialists
We don't actively do conversion rate optimization (CRO) consulting ourselves, nor do we run strategy audits. Instead, we act as the dedicated, high-performance technology partner for CRO strategy consultants and design agencies.
When you design complex variant matrices, bundle layouts, localized checkout experiences, or interactive filters to lift performance—our engineering team codes them cleanly, integrates them into the Shopify architecture, and guarantees they load instantly on mobile.
Pixel-Perfect Builds
Translating high-fidelity Figma design files, tests, and recommendations into clean Liquid blocks without app clutter.
Mobile-First Focus
Ensuring all dynamic tests, sliders, and checkout fields are fully optimized for small screens, accounting for 70%+ of traffic.
Zero Code Bloat
We don't rely on generic apps. We code optimization ideas directly into the theme for maximum performance and stability.
A/B Testing Support
Easily configure custom attributes, schema files, and hooks to integrate with testing platforms (VWO, Kameleoon, etc.).
Our Capabilities
We solve Shopify Plus engineering challenges.
A comprehensive suite of technical services to help ambitious ecommerce stores migrate, rebuild, and continuously improve.
Shopify Store Development
From high-growth brands on Basic to enterprise merchants on Plus — we build clean, fast, maintainable Shopify storefronts that scale with your business.
- Custom themes & OS 2.0
- Custom sections & blocks
- Collection & search UX
- Cart & checkout flows
Plan Migrations & Upgrades
Moving from Basic → Advanced → Plus, or from Magento/WooCommerce to Shopify? We handle the technical complexity of the transition end to end.
- Basic → Advanced → Plus
- Magento → Shopify migrations
- SEO & URL preservation
- App stack rationalisation
Performance Diagnostics
White-hat, root-cause approach. We identify exactly what is slowing your store — whether it's a third-party app, an unoptimised image pipeline, or a tracking pixel firing twice.
- App & script impact audit
- Core Web Vitals (LCP/CLS/INP)
- Mobile speed focus
- Real-user experience metrics
Shopify Markets & International
Launch across multiple countries with localised storefronts, multi-currency pricing, translated content, and Shopify Markets configuration.
- Shopify Markets setup
- Multi-currency & pricing
- Localised content & SEO
- International checkout flows
Custom Shopify Development
When standard Shopify capabilities aren't enough. We build custom app blocks, Shopify Functions, and API-driven experiences tailored to your business logic.
- Product configurators & builders
- Custom bundle & promotion logic
- Shopify Functions & Flow
- Admin & Storefront API
System Integrations
Connect Shopify to your ERP, CRM, inventory system, subscription engine, or any custom internal tool your business depends on.
- GraphQL & REST APIs
- Webhooks & Shopify Flow
- ERP / CRM / WMS sync
- Custom middleware layers
Headless & Mobile Commerce
For brands that need more control over their frontend — headless Shopify with a custom React/Next.js storefront, or native mobile commerce experiences.
- Headless Shopify (Next.js)
- Storefront API integration
- Mobile app development
- Hybrid PWA experiences
Ongoing Engineering Partner
We act as an extension of your team — shipping features, troubleshooting third-party apps, supporting campaigns, and evolving the store as your business grows.
- Retainer-based support
- App conflict troubleshooting
- Campaign & landing pages
- Technical consulting
Proven Outcomes
Selected Shopify Engineering Projects
We focus on building robust, high-converting platforms instead of simple templates.
Perk Clothing
Perk started on Shopify Basic and today operates on Shopify Plus. For over three years, CartScaler has been their dedicated remote engineering team — shipping new features, managing platform upgrades, building bundle and promotion mechanics, and continuously improving mobile performance as the brand has grown.
Apolis Global
Built a custom bag-personalization experience that connects seamlessly with Shopify’s cart and checkout. Powered by AWS Lambda, it is designed to scale reliably during traffic peaks. The same storefront supports wholesale and direct-to-consumer sales, with pricing, availability and purchasing experiences adapting to each buyer type.
Ecoy
Engineered scalable Shopify Plus storefront architecture with custom sections, streamlined subscription experience, and optimized mobile checkout for Australia's leading eco-bedding brand.
Bella Vita Luxe
With a strong existing presence in India, Bella Vita Luxe approached CartScaler to plan and execute their international scaling strategy. We built and launched storefronts across 6+ countries — including localised pricing, currency, content, and checkout flows — using Shopify Markets to manage the complexity without fragmenting the tech stack.
Ecosystem Expertise
Shopify Apps We Work With
We integrate and customize leading ecommerce platforms across marketing, reviews, subscriptions, experimentation, returns and fulfilment.
Marketing, CRM & SMS
Configuring complex email flows, subscriber syncs, and custom customer tracking schemas.
Klaviyo
Attentive
Postscript
SendlaneReviews, UGC & Loyalty
Integrating social proof, user-generated content sliders, and rewards interfaces smoothly.
Okendo
Judge.me
Yotpo
LooxSubscriptions & Cart
Developing seamless subscription portals and custom customer retention tools.
Skio
Recharge
Loop Subscriptions
SmartrrExperimentation & Optimization
Implementing A/B tests, pricing experiments, theme tests, and approved CRO variations.
Intelligems
VWO
ElevateClient Feedback
Trusted by brands
at every stage.
From growing Shopify stores to Shopify Plus—see what our clients say.
“We started on Shopify Advanced and CartScaler helped us plan and execute our transition to Plus without disrupting a single day of sales. They handled migrations, app audit, and checkout extensibility — while keeping the site fast throughout.”
Head of Ecommerce
8-Figure DTC Apparel Brand
“CartScaler ran a deep performance audit on our store. They isolated a single third-party reviews widget that was delaying our LCP by 1.8 seconds on mobile. Removing and replacing it properly added significant improvement to our conversion rate.”
Director of Technology
Global Health & Nutrition Brand
“They're our technical implementation partner for all CRO work. Our strategy team designs the tests and hypotheses, CartScaler builds them cleanly into the Shopify theme without introducing app dependencies or slowing the site down.”
VP of Growth & Optimization
International Cosmetics Retailer
“Launching across four countries with Shopify Markets felt complex until CartScaler took it on. They configured localised pricing, translated content architecture, and region-specific checkout flows — all in one clean deployment.”
CTO
Multi-Market D2C Brand
For Business Leaders
You don't need another development vendor. You need an engineering partner that translates storefront performance and design directly into commercial outcomes.
- —
Conversion Rate
Removing visual clutter, checkout friction, and sizing doubts.
- —
Storefront Speed
Maximizing SEO ranking and paid advertising return on investment.
- —
Merchandising Power
Allowing your marketing team to launch dynamic promotions & landing pages.
- —
Global Scaling
Unlocking international checkout support, multi-currency, and localized B2B setups.
For Tech & Product Teams
We speak your language. We write clean code, handle complex APIs, work with version control, and follow native Shopify architectures to minimize technical debt.
- —
Modern Architectures
Liquid templates, Online Store 2.0 components, and native app blocks.
- —
Shopify Functions & APIs
Custom checkout validations, discounts, and backend automated workflows.
- —
External Systems Sync
GraphQL, custom webhooks, ERP integrations, and serverless middleware.
- —
Optimized Performance
Refactoring layout shifts, asset sizes, and redundant tracking scripts.
The Difference
Why ambitious brands scale with CartScaler
Shopify Plus Focused
Shopify Plus and ecommerce engineering are at the core of our business. We understand the platform's limits and possibilities.
Business-aware
We don't ask 'what code should we write' first. We start with: 'what commercial outcome are we trying to achieve?'
Technical Depth
We write robust Liquid, use custom webhooks, work with GraphQL, write Shopify Functions, and integrate complex APIs.
Performance-conscious
We don't add apps to solve simple problems. We prefer native settings, configuration, and custom theme development.
Built to Maintain
We build clean code that doesn't break. Your in-house merchant team will still easily update sections six months later.
Long-term Partner
We act as your extended development team. We are committed to constantly improving and tweaking features post-launch.
How We Work
From ecommerce problem to production
Understand
We study your business, objectives, current storefront challenges, and target customer profiles.
Audit
We dive deep into your active theme code, apps list, pixel tracking scripts, and core web vitals.
Plan
We create a clear map detailing what should be configured natively, built custom, or completely removed.
Build
Our Shopify engineers write clean Liquid, CSS, and JS using modern best practices and minimal app overhead.
Test
Rigorous testing across desktop and mobile, checkout flows, variations, tracking scripts, and integrations.
Launch
Safe deployment with zero downtime, verified URL redirects, and immediate traffic monitoring.
Improve
Ongoing optimization of UX, page speed, customer conversion rates, and scaling capabilities.
About CartScaler
20+ years of engineering.
Focused on ecommerce.
CartScaler is the ecommerce-focused practice of OpenCubicles Technologies — a software engineering team with over 20 years of experience building production systems across custom web applications, ERP, CRM, Applied AI, mobile platforms, and enterprise integrations.
Our ecommerce journey started almost when Shopify did. We worked with Magento for years — we appreciated the open-source flexibility — but as Shopify matured into a platform capable of handling serious ecommerce complexity, we made a deliberate decision: ecommerce, exclusively on Shopify.
That depth of broader engineering experience is what separates us. When a Shopify store needs a custom AWS Lambda integration, a machine-learning-assisted recommendation engine, a complex ERP data sync, or a serverless checkout validation — we have built those systems before, outside ecommerce.
- →
Custom Applications & Platforms
Over two decades building bespoke web applications, SaaS platforms, and enterprise software from scratch.
- →
ERP, CRM & Business Systems
Deep experience integrating and building systems that connect commerce operations to the wider business.
- →
Applied AI & Machine Learning
Practical application of AI in product recommendation, demand forecasting, and intelligent automation.
- →
Mobile & Cross-Platform
Native Android and iOS apps, plus hybrid PWA experiences connected to commerce backends.
- →
Shopify — Exclusively for Ecommerce
A deliberate, focused choice. We understand the platform deeply — its capabilities, its limits, and how to extend both.
Frequently Asked Questions
Everything you need to know about working with CartScaler on Shopify engineering.