Principal UI Engineer Shopify

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

Job summary

A leading digital agency in the UK seeks an experienced Shopify Developer to lead the delivery of complex Shopify projects. The successful candidate will oversee architecture decisions, mentor developers, and collaborate closely with teams to deliver exceptional eCommerce solutions. A focus on performance, code quality, and scalability is essential. The role offers ownership and progression in a dynamic agency environment.

Qualifications

• Expert in Shopify development and eCommerce architecture.
• Strong understanding of performance, code quality, and scalability.
• Experience in leading technical teams and projects.

Responsibilities

• Lead technical delivery of complex Shopify projects.
• Own architecture decisions and code quality.
• Mentor developers and drive best practices.

Skills

Shopify development

JavaScript

TypeScript

OOP

eCommerce architecture

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.

Key Highlights

• Lead the technical delivery of complex Shopify projects across themes, apps, checkout, and headless builds
• Own architecture decisions, code quality, performance, and long-term maintainability
• Act as the go-to technical authority and escalation point for teams and clients
• Drive best practices in JavaScript/TypeScript, OOP, testing, and documentation
• Shape and improve development tooling, CI/CD pipelines, and local environments
• Mentor developers and set high standards for delivery across the team
• Partner closely with PMs, designers, and clients to deliver exceptional ecommerce solutions
• Work with cutting-edge Shopify features including GraphQL, Markets, Hydrogen/Oxygen, and checkout customisation

Ideal For Someone Who

• Is an expert in Shopify development and ecommerce architecture
• Enjoys solving complex technical challenges and leading by example
• Cares deeply about performance, code quality, and scalability
• Thrives in a client-facing, collaborative agency environment
• Wants real ownership, influence, and progression

Full Job Spec Available Upon Request