Engineering High-Performance Shopify Apps & Custom Storefronts.
Hi, I’m Nazmul Hawlader (NazmulCodes). I build published Shopify App Store applications (React/Polaris/GraphQL/Python) and hand-crafted Online Store 2.0 themes with zero page builder bloat, sub-second load speeds, and deep merchant customizability.
Published Shopify Apps in Production
Engineered from ground up with React, Shopify Polaris, App Bridge, GraphQL Admin APIs, and high-throughput Python / Node.js backends.
DemandMind
An AI/ML-driven inventory & sales prediction app embedded in Shopify Admin, processing merchant sales history to generate daily/monthly forecast models.
Stockly
Published Shopify embedded app (formerly Stock Alert) that monitors merchant inventory in real-time, automatically hides out-of-stock items to prevent overselling, and dispatches multi-channel alerts.
Shoppable Posts
Published Shopify App that empowers merchants to tag products directly in blog posts and editorial content, allowing instant cart additions without leaving articles.
EUR to BGN
Shopify App providing seamless live currency conversion between Bulgarian Lev (BGN) and Euro (EUR) with dual-price display compliance.
Featured Portfolio & Case Studies
Explore 33+ real-world Shopify embedded apps, bespoke Liquid storefronts, high-converting advertorials, and custom engineering projects.
DemandMind
An AI/ML-driven inventory & sales prediction app embedded in Shopify Admin, processing merchant sales history to generate daily/monthly forecast models.
Stockly
Published Shopify embedded app (formerly Stock Alert) that monitors merchant inventory in real-time, automatically hides out-of-stock items to prevent overselling, and dispatches multi-channel alerts.
Clinique Dentaire Aurea
Rebuilt dental clinic homepage into 11 hand-coded custom Liquid sections + header/footer with 369 theme settings, 0 page builder bloat, and Lighthouse 93 performance.
Shoppable Posts
Published Shopify App that empowers merchants to tag products directly in blog posts and editorial content, allowing instant cart additions without leaving articles.
Gum Health Magazine
Engineered a modular advertorial landing page template system with custom Liquid blocks, schema markup, and zero page builder dependencies for high-volume paid traffic.
LED Neon Flex
Developed a bespoke nested variant product configurator for commercial LED fixtures without monthly third-party app subscriptions, calculating live pricing and custom cuts.
B2B Be Sunset
Built a dedicated B2B wholesale portal with customer-tier verification, minimum order quantity rules, bulk quick-order matrix, and VAT validation.
Klense.nl
Built 3 high-converting landing pages for Dutch DTC brand Klense, featuring an interactive postcode-based water quality diagnostic tool.
EUR to BGN
Shopify App providing seamless live currency conversion between Bulgarian Lev (BGN) and Euro (EUR) with dual-price display compliance.
Reliv Products
Full homepage overhaul for a 35-year nutrition and wellness brand, introducing modern editorial typography, product clinical proof sections, and fluid responsive design.
Hempire Gardens
Diagnosed and resolved a broken Shopify Markets configuration and subfolder routing conflict for a UK CBD brand, restoring organic search equity.
Kind Laundry
Comprehensive site speed overhaul for eco-friendly DTC brand, eliminating legacy jQuery bottlenecks, fixing API refresh loops, and implementing native lazy loading.
Mallet London
Crafted bespoke homepage and collection showcase sections for British luxury footwear brand Mallet, emphasizing editorial imagery and product drops.
Gus* Modern
Collaborated on the custom Shopify theme development for contemporary furniture manufacturer Gus* Modern, supporting fabric swatch selections and retail locator.
Chlorophyll Water
Engineered brand-driven direct-to-consumer store for bottled wellness water, incorporating recurring subscriptions, press carousels, and retail store locator.
Plum Deluxe
Built subscription club onboarding, custom gift set bundling options, and seasonal sample pack selector for artisan tea purveyor.
Myant Health
Built healthcare technology e-commerce portal for biometric monitoring garments with medical device compliance notices and multi-tiered clinical packaging.
Urban Leaf
Full-scale store build for hydroponic gardening company, including custom kit builders, plant recommendation quiz, and wholesale inquiry funnel.
4E's USA
Commercial scientific equipment storefront with technical specification sheets, RFQ (Request for Quote) system, and bulk laboratory distributor discounts.
AHW Studio
Bespoke dark-themed e-commerce experience for Sydney-based handcrafted jewelry and horology studio, focusing on craftsmanship storytelling and custom engraving.
Brightlink AV
Commercial matrix switcher and video wall hardware catalog with interactive wiring diagram guides and system builder.
Broidr
Interactive apparel customization store allowing users to upload vector logos, choose thread colors, and preview embroidered apparel.
FitXR
Modern web portal for leading VR fitness app featuring class schedules, trainer profiles, Oculus/Meta hardware accessory bundles, and membership activation.
Grill Armor Gloves
Complete Shopify storefront overhaul for leading heat-resistant BBQ gear brand, featuring temperature rating comparison tables and bundle discounts.
Unify Patches
Resolved complex merchant account creation workflows, artwork upload validation, and custom patch proof approval pipelines for manufacturing business.
The Idea Space
Bespoke Shopify storefront for creative workspace platform, blending lifestyle merchandise with event ticket booking and membership subscriptions.
GeoRelief
German e-commerce store for 3D raised-relief geographical maps, featuring regional filters, frame configurators, and multi-language support.
Frome
Handcrafted ceramic and textile home goods store with story-rich artisan profiles, gift registry integrations, and warm earth-tone design.
Oush World
Converted a comprehensive 14-page high-fidelity prototype into a production-ready Shopify theme with subscription toggles and custom cart drawer.
Hasenbos Militaria
Configured specialized domestic (PostNL) and international shipping profiles with three tiers of custom high-value insurance and full Dutch localization.
The Cosy
Developed cozy lifestyle e-commerce store with product bundle builders, review widgets, and mobile-optimized conversion funnels.
My Hilu
E-commerce storefront for pure graphene temperature-regulating blanket, featuring thermal technology visualizations and size/color swatches.
GetCarTablet
High-converting vehicle compatibility checker and direct-response sales funnel for wireless Apple CarPlay and Android Auto car tablets.
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 Embedded & Public App Engineering
Full-stack Shopify applications built with React, Shopify Polaris, App Bridge, GraphQL, Node.js/Python FastAPI, and cloud-native databases. From AI forecasting engines to real-time inventory automation.
- Shopify Polaris UI & App Bridge v3 integration
- High-throughput GraphQL Admin & Storefront API querying
- Idempotent webhook queue processing (Redis / PostgreSQL)
- Shopify Recurring Application Charges (Billing API)
- GDPR compliance, OAuth 2.0 & App Store Submission readiness
Bespoke Liquid Themes (0 Page Builder Bloat)
Clean, modular Liquid section architectures built from Figma prototypes. No slow page builders (GemPages/PageFly/Shogun) that ruin load speeds. 100% merchant-editable through deep theme editor schema.
- Modular custom Liquid sections & reusable block schemas
- Zero-dependency native HTML/CSS/JS components
- Figma & Adobe XD pixel-perfect conversions
- Full WCAG AA accessibility compliance (contrast, keyboard nav, screen readers)
- Rich JSON-LD Structured Data for Google search snippets
Core Web Vitals & Speed Optimization
Surgical performance tuning for high-volume stores. Eliminate render-blocking scripts, refactor jQuery bloat, lazy-load media, and streamline the critical rendering path for maximum conversion.
- Cumulative Layout Shift (CLS) eradication (0.000 target)
- Largest Contentful Paint (LCP) reduction below 1.2 seconds
- Legacy jQuery removal and pure Vanilla JS refactoring
- Shopify CDN image optimization (WebP/AVIF srcsets)
- Third-party app script auditing, deferral, and unblocking
Direct-Response Funnels & Advertorials
Specialized landing pages engineered for media buyers and high-volume paid campaigns (Meta, TikTok, Google Ads). Modular advertorial layouts, interactive quizzes, postcode water report diagnostics, and sticky mobile conversion bars.
- Modular advertorial block architecture (custom editorial sections)
- Interactive lead-gen quizzes & postcode diagnostics (e.g. Klense)
- Sticky mobile buy bars with dynamic stock counters & variant swatches
- Clinical proof comparison matrices and trust proof tickers
- Sub-second page load times on mobile 4G networks for cold ad traffic
Complex Configurators, B2B & Custom Logic
Solve intricate business logic without expensive monthly app subscriptions. Custom product builders, nested variant option trees, B2B wholesale portals with tiered pricing, and international market routing.
- Multi-level nested product configurators (bypassing 100-variant cap)
- B2B wholesale gates, volume pricing, and bulk quick-order grids
- Shopify Markets internationalization & multi-currency routing
- Postcode diagnostics and interactive lead-generation calculators
- Custom subscription flows and dynamic bundle builders
Figma-to-Shopify & Platform Migrations
Convert complete multi-page design prototypes (10–20+ pages) into scalable, native Shopify themes with custom design tokens. Seamless platform migrations, Shopify Markets international routing, and 100% SEO link equity preservation.
- Complete 10–20+ page design system conversion (PDP, Collection, Cart, Account, FAQ)
- Clean CSS custom properties & fluid responsive layouts (320px–4K)
- Shopify Markets multi-currency & international URL consolidation
- 301 redirection maps preserving 100% SEO organic rankings
- Automated Metafields & Metaobjects schema configuration
Interactive Cost & Timeline Calculator
Configure your technical requirements to receive an instant timeline estimate and proposed budget range for your project.
Skills & Technology Stack
A battle-tested technology toolkit designed for high-conversion storefronts, compliant Shopify apps, and robust server architectures.
Shopify Core Ecosystem
Front-End & Modern Web
Backend, AI & Cloud Infrastructure
Trusted by Founders & Engineering Leaders
What clients, product managers, and Shopify store owners say about working with Nazmul.
"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 bridged our Python machine learning prediction backend with a beautiful React Polaris frontend in Shopify admin, handled GraphQL rate limits like a master, and built dynamic seasonal toolkits. Truly an elite Shopify App 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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