Lead / Senior Full Stack Software Engineer

Onstate Ltd; Leeds; Hybrid; GBP 60,000 - 75,000; Full time

Benefits offered by this job

Cash back medical care

Pension contribution 5%/3%

25 days holidays + birthday off

Mac or PC provided

Process development and R&D time

Company events

On-site parking

Work from home flexibility

Job summary

Onstate Ltd is a Leeds-based Shopify agency seeking a Lead/Senior Full Stack Shopify Developer. You will push Shopify to its limits, define technical strategy, and own delivery across high-stakes projects in a hybrid setup.

You should bring 5+ years in JavaScript, deep Shopify knowledge, and experience with cloud and AI tooling. Collaboration with cross-functional teams and emphasis on scalable, maintainable systems are essential.

Qualifications

• 5+ years experience in JavaScript.
• Strong knowledge of Shopify and building around its limits.
• Experience with serverless tech and cloud platforms (AWS/GCP/Azure).
• Experience with AI tools and knowing when to use them effectively.
• Experience with Drupal or Umbraco CMS.
• Solid understanding of user stories and agile workflows.
• Experience with Test Automation, TDD, or BDD.

Responsibilities

• Architect and push Shopify to its limits.
• Define technical approach and own processes.
• Deliver reliable, scalable, maintainable systems.
• Collaborate with multidisciplinary teams on multiple high-stakes projects.
• Lead the technical delivery and align with strategy.
• Design robust tech solutions and maintainable codebases.
• Translate scope into clear technical briefs and docs.
• Champion new technologies and standards.
• Educate team on bleeding-edge technology.
• Collaborate with PMs, design, and data & insight.
• Manage sprint burndowns and communicate budget impacts.
• Provide feedback on UI/UX and guide designs around Shopify limits.
• Define core development processes and best practices across the agency.

Skills

Shopify expertise

JavaScript (ES6+)

NodeJS

Serverless computing

AI tool usage

Agile / User stories

Tools

Shopify

AWS

GCP

Azure

Drupal

Umbraco

REST

TDD/BDD

Serverless

CI/CD

Job description

Salary: £60,000 - 75,000 per year

Requirements:

• We are looking for a Lead/Senior Full Stack Shopify Developer who understands the commercial realities of e-commerce and takes pride in the quality of our engineering.
• Strong knowledge of Shopify, including its capabilities, quirks, and how to build custom workarounds when it hits its limits.
• 5+ years experience in JavaScript.
• Strong knowledge of NodeJS and Vanilla JavaScript (ES6+).
• Experience with serverless technology and deploying cloud functions.
• Experience with AI tools and knowing when and where to use them effectively.
• Experience with cloud platforms such as AWS, GCP, or Azure.
• Experience working with enterprise CMS platforms such as Drupal or Umbraco.
• A solid understanding of User Stories and agile workflows.
• Experience with Test Automation, TDD, or BDD.

Responsibilities:

• Architect and build solutions that push Shopify to its limits.
• Define our technical approach and take ownership of our processes.
• Ensure we deliver reliable, scalable, and maintainable systems.
• Work within multidisciplinary teams across multiple high-stakes projects.
• Lead the technical delivery of projects while keeping a close eye on our strategy.
• Design robust technology solutions and maintainable codebases.
• Convert complex scope into clear technical briefs and comprehensive project documentation.
• Champion new technologies and standards.
• Educate yourself and your team on bleeding-edge technology.
• Collaborate cross-functionally with project management, design, and data & insight.
• Manage team sprint burndowns, communicate budget impacts, and refine project scope with the PMs.
• Provide constructive feedback on UI/UX, suggest innovations, and guide designs around Shopifys technical limitations.
• Champion user value by defining what data we need to collect, how we collect it, and why it matters.
• Define, refine, and communicate our core development processes and best practices across the agency.

Technologies:

• AI
• AWS
• Architect
• Azure
• Cloud
• CMS
• Drupal
• ES6
• GCP
• JavaScript
• NodeJS
• REST
• Serverless
• Shopify
• TDD
• Umbraco
• UX UI Design
• Support
• Fullstack

More:

We are Onstate, a specialist Shopify agency based in Leeds with a hybrid approach, and most of our team works in the office two to three days a week with flexibility to work remotely the rest of the time. We take on complex, high-scale Shopify projects, including large product catalogues, custom systems, and highly personalised customer journeys. We deliver work through Discover, Define, Deliver, and Deploy, and we continually refine how we work. We offer a salary of £60,000 to £75,000, cash back medical care, a 5%/3% pension contribution, 25 days holiday plus your birthday off, a Mac or PC based on preference, dedicated time for process development and R&D, company events, on-site parking, and work from home flexibility.

last updated 36 week of 2026