Usama Rehman Book a retainer

Based in Pakistan — Working remotely with international brands and agencies

I build custom Shopify theme sections, AJAX cart flows, and full-stack web software.

By day I ship Liquid templates, subscription selling-plan pickers, and high-converting storefronts on Dawn, Savor, and Rise at a digital agency. Beyond the storefront layer, I architect multi-tenant SaaS platforms, REST and GraphQL APIs, and Million-row Python data pipelines.

Book a monthly retainer Read top 3 case studies

Storefront stack: Liquid, vanilla JavaScript, AJAX Cart API, selling plans, Dawn, Savor, Rise, and custom sections.

Application stack: Python (Django, FastAPI, Strawberry GraphQL), Node.js (Express), React, TypeScript, PostgreSQL, MongoDB, Docker.

sections/main-product-ascension.liquid
Ascension Labs Cellular NAD+ Serum amber dropper bottle and refill pod
SKU: ASC-NAD-30 — 30 ml / 1.0 fl oz Glass Dropper

Ascension Labs NAD+ Cellular Serum

$57.80 $68.00 Save 15% on auto-delivery
Formulated with 12% liposomal NAD+ precursor and 5% pharmaceutical-grade niacinamide. Bound directly to Shopify product metafields so merchants edit clinical specs per SKU inside the theme editor.
1
$42.20 away from complimentary shipping 58%
AJAX Cart (1 item) — Subtotal $57.80

Shopify theme architecture

Dawn, Savor, and Rise custom builds, OS 2.0 JSON templates, and merchant-editable section schemas.

AJAX cart & selling plans

Subscription pickers, slide-out cart drawers, tiered shipping bars, and bundle upsells in vanilla JS.

Full-stack web engineering

Django + Strawberry GraphQL, FastAPI, Node.js/Express REST APIs, React + TypeScript, and Docker.

Data & RBAC systems

Multi-tenant SaaS access control, JWT hierarchies, and Python ETL pipelines processing 1M+ records.

Selected work

Storefront builds and custom Liquid sections come first, followed by multi-tenant full-stack software and high-volume data engineering.

Showing 11 projects

Ascension Labs

Shopify custom section
Liquid / Vanilla JS / Selling Plans

Built a custom product page section featuring a metafield-driven accordion description and a native subscription selling-plan picker.

Read case study

DÉPRIMÉ

deprime.shop
Shopify Liquid / Custom Theme / CSS Grid

Redesigned the homepage for an anime-inspired streetwear brand with custom editorial lookbook blocks and fast collection merchandising.

Read case study

Sportsmode

sportsmode.us
Shopify Savor Theme / Liquid / JS

Executed a complete homepage revamp on the Savor theme, restructuring hero promotions, featured collections, and mobile navigation ergonomics.

Visit sportsmode.us

Trappanda

trappanda.com
Shopify Liquid / Vanilla JS / CSS

Engineered the sticky header, hero banner, visual category navigation, New and Hot product showcase, and Instagram feed sections.

Visit trappanda.com

Jewelify World

jewelifyworld.com
Shopify Rise Theme / Liquid / Metafields

Full storefront build on the Rise theme tailored for fine and everyday jewelry cataloging, variant swatches, and mobile checkout flow.

Visit jewelifyworld.com

ISSUED

Streetwear storefront
Shopify OS 2.0 / Liquid / AJAX Cart

End-to-end streetwear store build with custom typography settings, drop-ready product templates, and zero-bloat vanilla JS interactions.

Commercial Shopify Theme Sections

Etsy digital shop
Liquid / Self-Contained Schema / Dawn

Authored and packaged standalone, plug-and-play Shopify OS 2.0 sections sold directly to merchants and agencies on Etsy.

Hanzalah School System

Multi-tenant SaaS
Django / Strawberry GraphQL / React / TS / URQL

Architected a multi-tenant school management SaaS with role-based access control, typed GraphQL schema, Vite + React + TypeScript frontend, and Tailwind CSS.

Read case study

Dealer Pro

Backend & RBAC API
Node.js / Express / REST API / JWT Roles

Built the Node.js and Express backend service exposing structured REST APIs guarded by multi-level JWT role middleware.

High-Volume 1M+ Record ETL Pipeline

Data engineering
Python / Selenium / ijson / MongoDB

Engineered an automated extraction and transformation pipeline capable of streaming and indexing over 1,000,000 records into MongoDB with constant memory footprint via ijson.

FastAPI & Async Service Backends

Python / FastAPI / Docker
FastAPI / Python / PostgreSQL / Docker

Designed containerized Python microservices and asynchronous API layers connecting frontend dashboards with relational and document data stores.

In-depth case studies

A closer look at the technical brief, implementation architecture, stack, and outcomes across my top three Shopify and full-stack engagements.

Ascension Labs — Custom Product Section & Subscription Picker

Shopify Storefront Engineering
Ascension Labs custom product page architecture diagram illustrating selling plan radio allocations and metafield accordions
Architecture schematic of sections/main-product-ascension.liquid Liquid + Selling Plans API + AJAX Cart

The brief

Ascension Labs needed a custom Shopify product page section that presented dense product details cleanly without overwhelming mobile shoppers, while making recurring subscription options (selling plans) effortless to understand and select above the fold.

What I built

I built a self-contained Liquid product section pairing an accessible, collapsible accordion description with a custom selling-plan picker widget. Switching between one-time purchase and subscription dynamically recalculates unit pricing, updates the active selling_plan input, and posts directly to Shopify’s AJAX Cart API without third-party script bloat.

The stack

Shopify Liquid, Vanilla JavaScript, Shopify Selling Plans API, AJAX Cart API (/cart/add.js), CSS Custom Properties, OS 2.0 Section Schema.

The outcome

Shipped a merchant-configurable product section where non-technical team members manage accordion panels, metafield specifications, and subscription copy directly from the Shopify Theme Editor without external app lock-in.

DÉPRIMÉ (deprime.shop) — Streetwear Homepage Redesign

deprime.shop
DEPRIME anime-inspired streetwear homepage layout diagram
Storefront layout breakdown for DÉPRIMÉ (deprime.shop) Visit live store at deprime.shop

The brief

DÉPRIMÉ (deprime.shop), an anime-inspired streetwear brand, needed a homepage redesign that matched the visual intensity of their apparel drops instead of looking like a default Shopify template.

What I built

I redesigned and coded the homepage in modular Liquid sections with art-directed responsive imagery, editorial collection grids, and streamlined product cards so new seasonal drops can be staged and launched inside the Shopify Theme Editor.

The stack

Shopify Liquid, Vanilla JavaScript, Responsive CSS Grid, Shopify OS 2.0 JSON Templates, Lazy-Loaded Responsive Media.

The outcome

Delivered a distinctive, brand-native storefront live at deprime.shop that gives the founders full control over seasonal collection drops and lookbook layouts without touching code.

Hanzalah School System — Multi-Tenant School Management SaaS

Full-Stack SaaS Architecture
Hanzalah School System multi-tenant Django Strawberry GraphQL and React TypeScript URQL architecture diagram
Multi-tenant GraphQL & role-based access architecture Django + Strawberry GraphQL + React + URQL

The brief

Educational institutions needed a unified, cloud-hosted SaaS platform capable of isolating data across multiple school tenants while enforcing granular permissions for administrators, teachers, accountants, and students.

What I built

I engineered the multi-tenant backend using Django and Strawberry GraphQL with strict role-based access control (RBAC), paired with a fast single-page frontend built in React, TypeScript, Vite, URQL, and Tailwind CSS.

The stack

Python, Django, Strawberry GraphQL, React, TypeScript, Vite, URQL, Tailwind CSS, PostgreSQL, Docker.

The outcome

Established an end-to-end typed GraphQL contract between the Django backend and React/TypeScript frontend with strict tenant isolation and role-gated administrative, faculty, and student workflows.

How we can work together

Whether you run a growing DTC brand that ships storefront updates every week or an agency looking for a dependable senior engineer, I work in clear, predictable structures.

Monthly Shopify retainer

Ongoing front-end engineering for DTC brands and agencies that want continuous conversion improvements without hiring a full-time in-house developer.

  • Custom OS 2.0 Liquid sections & landing pages
  • AJAX cart drawers, tiered gifts & upsell logic
  • Selling-plan subscription widgets & bundles
  • Core Web Vitals & script cleanup on Dawn/custom themes
Inquire about retainer availability

Fixed-scope theme builds & revamps

Complete homepage revamps, custom product templates, or full store builds on Dawn, Savor, Rise, or bespoke architectures.

  • Pixel-accurate Figma to Shopify Liquid builds
  • Metafield-driven product templates & size guides
  • Sticky headers, megamenus & filtering UX
  • Clean merchant documentation for your team
Request a fixed-project quote

Full-stack & backend engineering

Custom web applications, API backends, and data pipelines when your business logic outgrows off-the-shelf plugins.

  • Django, FastAPI & Strawberry GraphQL backends
  • Node.js/Express REST APIs with multi-role JWT auth
  • React + TypeScript frontends with URQL/Tailwind
  • Python, Selenium & MongoDB ETL pipelines
Discuss a full-stack role or build

How I ship without breaking live revenue

Every storefront feature or backend service follows a four-step engineering workflow so your live checkout stays protected.

  1. Step 1

    Codebase & theme audit

    I inspect your current Liquid templates, third-party app scripts, or API schema first, identifying bottlenecks before writing a line of code.

  2. Step 2

    Isolated staging branch

    All work happens in a duplicate Shopify preview theme or Dockerized staging environment with clean, modular commits.

  3. Step 3

    Cart, viewport & keyboard QA

    I test variant switching, selling-plan allocations, AJAX cart drawer states, and responsive breakpoints from 360px mobile up to desktop.

  4. Step 4

    Merchant handover & iteration

    Every section ships with intuitive Theme Editor schema controls so your team can update copy, images, and blocks without developer intervention.

About Usama Rehman

I am a software engineer based in Pakistan, working remotely with e-commerce brands, digital agencies, and engineering teams. I hold a BS in Software Engineering from the University of Sindh and previously served as a web development instructor—an experience that shaped how I structure code, document theme schemas, and explain technical trade-offs clearly to non-technical stakeholders.

In my current agency role as a Shopify front-end developer, I work directly inside production themes—building custom Liquid sections, bespoke Dawn, Savor, and Rise storefronts, selling-plan subscription flows, and zero-dependency vanilla JavaScript cart drawers.

Unlike front-end specialists who stop at the template layer, I also build the systems underneath: multi-tenant SaaS applications in Python/Django and Strawberry GraphQL, high-concurrency APIs in FastAPI and Node.js/Express, interactive frontends in React and TypeScript, and Python ETL pipelines that process over a million records into MongoDB and PostgreSQL.

Current focus Shopify Front-End Developer (Agency) & Retainer Consultant
Shopify stack Liquid, Vanilla JS, AJAX Cart API, Selling Plans, Dawn, Savor, Rise, OS 2.0 JSON Schemas
Backend & APIs Python (Django, FastAPI, Strawberry GraphQL), Node.js, Express, REST, JWT RBAC
Frontend & SPA React, TypeScript, Vite, URQL, Tailwind CSS, Semantic HTML5, WCAG AA
Data & DevOps PostgreSQL, MongoDB, Python ETL (Selenium, ijson), Docker
Education BS Software Engineering — University of Sindh
Teaching Former Web Development Instructor
Location Pakistan (Remote worldwide, flexible overlap with US/UK/EU/PKT)

Start a conversation

Available for monthly Shopify retainers, custom theme builds, and full-stack engineering roles. Send a note below or email me directly.

Direct contact

Prefer email without a form? Click below to open your mail client directly.

Domain: usamarehman.com