Hi, I'm Muhammad W Tahir, a Senior Shopify Engineer with 11 years of experience delivering deep theme customization, third-party app integration, and performance optimization for high-traffic storefronts. I recently achieved a 22-point Lighthouse performance score improvement by implementing lazy loading, inline critical CSS, and WebP image delivery. My work spans Shopify theme architecture, GraphQL and REST API integration, checkout extensibility, and CI/CD-driven deployment. I love collaborating with cross-functional teams to design scalable solutions that improve reliability and conversion. I also mentor engineers on best practices for Liquid templates, API performance profiling, and resilient deployment pipelines.

Muhammad W Tahir

Hi, I'm Muhammad W Tahir, a Senior Shopify Engineer with 11 years of experience delivering deep theme customization, third-party app integration, and performance optimization for high-traffic storefronts. I recently achieved a 22-point Lighthouse performance score improvement by implementing lazy loading, inline critical CSS, and WebP image delivery. My work spans Shopify theme architecture, GraphQL and REST API integration, checkout extensibility, and CI/CD-driven deployment. I love collaborating with cross-functional teams to design scalable solutions that improve reliability and conversion. I also mentor engineers on best practices for Liquid templates, API performance profiling, and resilient deployment pipelines.

Available to hire

Hi, I’m Muhammad W Tahir, a Senior Shopify Engineer with 11 years of experience delivering deep theme customization, third-party app integration, and performance optimization for high-traffic storefronts. I recently achieved a 22-point Lighthouse performance score improvement by implementing lazy loading, inline critical CSS, and WebP image delivery. My work spans Shopify theme architecture, GraphQL and REST API integration, checkout extensibility, and CI/CD-driven deployment.

I love collaborating with cross-functional teams to design scalable solutions that improve reliability and conversion. I also mentor engineers on best practices for Liquid templates, API performance profiling, and resilient deployment pipelines.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
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Language

English
Fluent

Work Experience

Senior Software Engineer at WTW
June 1, 2021 - May 31, 2026
Designed a modular Shopify theme architecture using Liquid, JavaScript, and CSS custom properties to support white-label storefronts for multiple insurance product lines, enabling tenant-specific branding without code duplication. Built a GraphQL integration layer connecting Shopify storefronts to an internal policy administration REST API, implementing idempotent order creation and resilient retry logic for high-value insurance transactions. Modernized checkout extensibility by migrating legacy jQuery scripts to a React-based Shopify app block, improving script load performance and reducing custom checkout JavaScript payload by 40%. Tuned Core Web Vitals across the broker enrollment storefront by implementing lazy loading, critical CSS inlining, and WebP image delivery, achieving a 22-point Lighthouse performance score improvement. Integrated a third-party quoting engine via Shopify Functions and webhook consumers, isolating vendor-specific failures to prevent cart abandonment during
Software Engineer at UnitedHealth Group
January 1, 2017 - June 30, 2021
Developed a member-facing benefits enrollment portal using Angular and a C# .NET Core REST API, handling plan selection logic and real-time eligibility verification. Improved form validation and responsive layout for the Medicare plan comparison tool, ensuring WCAG 2.0 AA compliance across desktop and mobile viewports. Extended an internal provider search service by adding geolocation filtering and appointment availability caching, reducing average search latency by 30%. Contributed to a HIPAA-compliant data pipeline that anonymized member activity logs for analytics, using SQL Server Integration Services and Python transformation scripts. Supported production incident resolution for the enrollment system during annual open enrollment, diagnosing race conditions in session management and deploying a hotfix.
Junior Application Developer at IBM
July 1, 2015 - October 31, 2016
Built interactive dashboard components for an internal resource management tool using AngularJS and a C# .NET Web API backend. Implemented server-side pagination and sorting for large datasets in SQL Server, improving page load times for resource allocation views. Wrote unit and integration tests for REST endpoints using NUnit and Moq, increasing API test coverage for the scheduling module. Assisted in migrating legacy ASP.NET Web Forms pages to a single-page AngularJS application, ensuring feature parity during the phased rollout.

Education

Bachelor's Degree in Information Science and Technology at Penn State Abington
January 1, 2011 - January 1, 2015

Qualifications

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Industry Experience

Software & Internet, Professional Services, Healthcare