Senior UI Engineer (Shopify)

IDHL Group; Leeds; On-site; GBP 100,000 - 125,000; Full time

Job summary

A digital agency in the United Kingdom seeks a Senior UI Engineer to lead multiple projects and teams. The ideal candidate will oversee frontend architecture, maintain high coding standards, and mentor developers. Responsibilities include building scalable Shopify solutions and collaborating with various stakeholders to enhance user-focused digital experiences. The role emphasizes a performance-oriented mindset and offers real ownership and career progression.

Benefits

Ownership and autonomy

Focus on quality and career progression

Qualifications

• Strong experience with Shopify, including themes, apps, APIs, and GraphQL.
• Advanced JavaScript/TypeScript skills with solid OOP fundamentals.
• Experience with headless commerce and performance optimization.

Responsibilities

• Build scalable Shopify solutions for themes, apps, checkout, and headless builds.
• Own features from technical design to delivery and support.
• Collaborate with designers and PMs for excellent e-commerce experiences.
• Mentor teammates and improve development standards.

Skills

Shopify expertise

Advanced JavaScript skills

TypeScript skills

OOP fundamentals

Performance optimization mindset

Git workflow

CI/CD pipeline experience

Tools

Webpack

Yarn

Gulp

Job description

Who are IDHL?

At IDHL, we’re more than a digital agency, we’re a strategic partner to ambitious brands, helping them accelerate growth in the digital economy.

Our expertise is delivered through three core divisions: Performance, Web & eCommerce, and Intelligence – all working closely together to create impact across channels.

We’re also home to Fostr, a Shopify Plus agency for luxury and lifestyle brands, and The MTM Agency, specialists in integrated marketing and audience engagement.

What connects it all is our focus on outcomes, not just outputs. We back each other, take pride in what we do, and make sure the way we work works for everyone.

Senior UI Engineer

As a Senior UI Engineer, you’ll operate as a technical leader across multiple projects and teams, shaping frontend architecture, enforcing platform-wide standards, and mentoring developers at all levels. You’ll play a critical role in ensuring code quality, consistency, and performance across the frontend practice, while collaborating with designers, backend developers, and stakeholders to deliver user‑focused digital experiences. This is a senior technical role for developers who combine deep expertise with strong communication and leadership skills.

What You’ll Do

• Build high-quality, scalable Shopify solutions across themes, apps, checkout, and headless builds
• Own features end-to-end — from technical design to delivery and support
• Collaborate closely with designers, PMs, and clients to deliver excellent e‑commerce experiences
• Champion clean code, performance, testing, and documentation
• Mentor teammates and contribute to better development standards and tooling

What You’ll Bring

• Strong experience with Shopify (themes, apps, APIs, checkout, Markets, and GraphQL)
• Advanced JavaScript / TypeScript skills and solid OOP fundamentals
• Experience with headless commerce (Hydrogen, Oxygen, or React‑based frameworks)
• Performance‑focused mindset, including Lighthouse optimisation
• Confident Git workflow and experience with CI/CD pipelines

Nice to Have

• Experience with Gadget.dev, Shopify POS, or B2B features
• Knowledge of modern build tools (Webpack, Yarn, Gulp, etc.)
• Shopify certifications (or willingness to work toward them)

Why Join Us

• Work on varied, high‑impact e‑commerce projects
• Real ownership, trust, and autonomy
• Strong focus on quality, learning, and career progression

Full Job Spec Available Upon Request