Senior Developer UIO

Were looking for a Senior Developer to join our eCommerce Technical team based from the NEXT Head Office in Leicestershire!

The Role:

Are you an experienced front-end specialist passionate about creating seamless high-converting digital experiences

Our eCommerce Tech team is looking for a Senior Front-End Developer to help evolve an enterprise digital platform serving over 8 million customers globally. Supported by central tech teams we build and manage the NEXT and Total Platform websites and mobile applications - all developed in-house.

Joining our User Interface Optimisation Team you will take a lead role in delivering high-impact functionality driven by Conversion Rate Optimisation (CRO) rigorous A/B testing and deep customer journey analysis.

In this position you will work within an agile collaborative team alongside talented developers to refine and build upon a quality-centric eCommerce platform. You will bridge technical execution and commercial strategy using data-driven experimentation to shape customer-facing features that directly influence multi-million-pound product investment decisions.

What Youll Take On

• Experimental Feature Architecture: Maintain architect and deploy high-performing client-side experimental features within the Bloomreach Digital Experience Platform (DXP). You will build rapid time-limited tests designed to achieve statistical significance and drive key business insights.
• Technical Execution & Overrides: Intercept override and inject custom features using HTML CSS and modern JavaScript. You will establish best practices for performance ensuring injection scripts run smoothly without causing layout shifts impacting Core Web Vitals or creating technical debt for base platforms.
• Technical Leadership & Quality: Drive code quality readability and modularity across the team. You will lead code reviews champion performance standards and ensure web accessibility standards (WCAG) are met across all responsive viewports.
• Continuous Improvement: Continuously evaluate and modernise workflows and practices to maximize developer productivity efficiency and feature velocity.
• Collaboration & Stakeholder Management: Translate complex technical concepts clearly for non-technical commercial and product stakeholders. Mentor and guide mid-level and junior developers and contribute to out-of-hours support during peak trading events (e.g. Black Friday and seasonal sales).

What Youll Bring:

• Core Techology Mastery: Deep hands-on experience with modern JavaScript semantic HTML5 and advanced CSS/SASS architecture.
• Framework Experience: Practical expertise with modern JavaScript frameworks and libraries.
• Experimentation & CRO: A solid understanding of client-side A/B testing DOM manipulation/injection and conversion rate optimisation principles.
• Performance & Accessibility: Proven success in optimizing Core Web Vitals UI performance profiling and WCAG accessibility standards.
• Analytics & Insight: Practical experience with web analytics platforms (e.g. Google Analytics 4) paired with strong analytical and problem-solving skills to assess experiment results.
• Leadership & Communication: A track record of mentoring junior and mid-level engineers leading technical discussions and presenting clearly to commercial partners.
• Collaborative Delivery: Experience working effectively within a large-scale fast-paced multifunctional technical environment across responsive multi-viewport platforms.
• Bonus experience: Familiarity with Azure DevOps service-oriented architecture or enterprise DXPs like Bloomreach.
  Discover how you can shape the future of our eCommerce platforms and build a career with space to grow - apply now.

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