Specialized Shopify Engineering Services
From official Shopify App Store apps and custom direct-response funnels to speed optimization and complete Figma-to-theme migrations.
Shopify App Development (Public & Custom Embedded)
Full-stack Shopify applications built with React, Shopify Polaris, App Bridge, GraphQL Admin APIs, Node.js/Python, and cloud-native databases. From public multi-tenant App Store SaaS to proprietary private apps tailored to unique merchant workflows.
- Shopify Polaris UI & App Bridge v3 seamless admin integration
- High-throughput GraphQL Admin & Storefront API querying
- Idempotent webhook queue processing (Redis BullMQ / PostgreSQL)
- Shopify Recurring Application Charges (Billing API) & OAuth 2.0
- GDPR/CCPA mandatory compliance webhooks & App Store submission
Custom Shopify Theme Development (Online Store 2.0)
Clean, modular Liquid section architectures built from Figma prototypes or custom requirements. Zero slow page builders (GemPages, PageFly, Shogun) that ruin store load times. 100% merchant-editable through deep theme editor schema.
- Custom Liquid section architecture with reusable block schemas
- Zero-dependency native HTML5, modern CSS & Vanilla JS components
- Pixel-perfect conversion from Figma, Adobe XD & Sketch designs
- Mobile-first responsive layouts meticulously tested (320px–4K)
- WCAG AA accessibility & built-in JSON-LD Structured Data
Shopify Automation, Flow Workflows & Payment Gateways
Automate repetitive store operations, inventory syncing, and customer notifications using Shopify Flow, custom webhooks, and third-party integrations. Full configuration of Shopify Payments, Stripe, PayPal, and regional gateways with multi-currency support.
- Shopify Flow custom trigger, condition & action automation workflows
- Shopify Payments, Stripe, PayPal & local gateway setup & testing
- Multi-currency & international market routing via Shopify Markets
- Automated inventory restock, low-stock & order fulfillment triggers
- Webhook dispatchers to Slack, Klaviyo, Asana, Google Sheets & ERPs
Shopify Bug Fixes & Checkout Troubleshooting
Swift, surgical diagnosis and repair of broken Shopify functionality. Fix Liquid syntax errors, JavaScript conflicts, broken cart drawers, mobile layout glitches, and Shopify Checkout Extensibility issues before they cost you sales.
- Liquid syntax error repair and missing template recovery
- JavaScript console error debugging & jQuery conflict resolution
- Shopify Checkout Extensibility & One-Page Checkout customization fixes
- AJAX mini-cart drawer errors, sticky buy button & variant selector glitches
- Third-party app conflict auditing and script cleanup
Shopify 301 Redirects, Broken URL Fixes & SEO Migration
Prevent traffic drops and ranking losses during store redesigns or platform migrations (WooCommerce/Magento to Shopify). Comprehensive audit of broken URLs, automated bulk 301 redirection maps, and canonical hierarchy enforcement.
- Full website crawl & 404 broken URL discovery audit
- Bulk 301 redirect URL mapping with wildcard regex pattern matching
- Legacy platform URL migration (WooCommerce, Magento, BigCommerce)
- Google Search Console coverage error remediation & sitemap validation
- Canonical tag auditing to eliminate duplicate content penalties
Core Web Vitals & Sub-Second Speed Optimization
Surgical performance tuning for high-volume stores. Eliminate render-blocking scripts, refactor bloated libraries, optimize Shopify CDN media, and streamline the critical rendering path for maximum conversion rate and organic SEO lift.
- Cumulative Layout Shift (CLS) eradication (0.000 target)
- Largest Contentful Paint (LCP) reduction below 1.2 seconds
- Legacy jQuery removal and pure modern Vanilla JS refactoring
- Shopify CDN responsive image optimization (WebP/AVIF srcsets)
- Third-party app script auditing, deferral, and unblocking
Core Engineering & Topics We Cover
In-depth architecture breakdowns, performance case studies, and engineering solutions across the modern Shopify and web stack.
Shopify Core Ecosystem
Front-End & Modern Web
Backend, AI & Cloud Infrastructure
Trusted by Founders & Engineering Leaders
Feedback from founders, e-commerce managers, and store owners on theme speed, custom apps, and technical execution.
"Nazmul delivered an extraordinary custom homepage on Shopify with 11 custom Liquid sections. We needed total flexibility to update our clinical procedures and copy without touching code, and he gave us 369 customizable settings! The speed is blazing fast (Lighthouse 93) and the zero-JS accordion for our SEO FAQ was genius."
"Working with Nazmul on our Shopify App Store application was seamless. He engineered a beautiful React Polaris frontend in Shopify Admin, connected to our prediction endpoints, handled GraphQL queries cleanly, and built responsive data tables. Truly a top-tier Shopify frontend engineer."
"Nazmul is our go-to senior developer for our most complex Shopify projects. On Myant Health, he engineered custom clinical compliance disclaimers, biometric sizing assistants, and responsive sections with immaculate Liquid code and zero delivery delays."
"Nazmul developed our 3 campaign landing pages including our custom Dutch postcode water quality diagnostic tool. Our lead capture rate jumped to over 18% immediately. His attention to mobile performance and conversion-driven UI is top-tier."
"Nazmul delivered flawless custom swatch selectors, spec matrices, and streamlined our customer PDP experience. Clean code, zero page builder bloat, and extraordinary communication throughout."
"Nazmul stepped in and completely stabilized our Shopify App Store application. He resolved our recurring billing webhook lifecycle, built an isolated shadow-DOM variant selector with zero theme CSS bleed, and guided us through official Shopify App Store approval."
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