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# Lead CRO Developer

- **Company:** Hackajob Ltd
- **Location:** Leeds, UK
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** HTML, JavaScript (Programming Language), A/B Testing, Data Analysis, Computing Platforms, Browser Compatibility, Code Review, Responsive Web Design, Web Performance Optimization, Web Platforms, Web Usability, Adobe Target, Optimizely
- **Published:** October 22, 2026
- **Apply:** https://www.totaljobs.com/job/senior-software-engineer/hackajob-ltd-job108213016

## About the Role

* Extensive experience developing A/B tests, personalisation campaigns or optimisation solutions within a commercial environment.
 * Expert knowledge of JavaScript, HTML and CSS, with a strong understanding of modern web development principles.
 * Experience working with experimentation platforms such as Optimizely, Adobe Target, VWO, AB Tasty or similar.
 * Proven leadership experience, including mentoring developers, leading technical discussions and promoting engineering best practice.
 * Strong understanding of website performance, accessibility, cross-browser compatibility and responsive design.
 * Experience working alongside UX, Product and Analytics teams throughout the experimentation lifecycle.
 * Excellent problem-solving skills with a passion for delivering measurable improvements to customer experience and commercial performance.
 * Strong communication and stakeholder management skills, with the ability to explain technical concepts to both technical and non-technical audiences.

## Description

* Lead the technical delivery of A/B and multivariate tests, ensuring high-quality, performant and scalable implementations across our digital platforms.

Build Optimisation Experiences:

 * Develop customer experiences using JavaScript, HTML and CSS, creating experiments and personalisation campaigns that improve conversion and user engagement.

Partner Across the Business:

 * Work closely with UX, Analytics and Marketing teams to translate ideas into measurable experiments and optimisation opportunities.

Drive CRO Best Practice:

 * Champion experimentation methodologies, coding standards and technical governance, ensuring reliable and statistically sound test implementations.

Optimise Performance:

 * Ensure experiments have minimal impact on page performance, accessibility and Core Web Vitals while maintaining an excellent customer experience.

Technical Leadership:

 * Mentor developers, conduct code reviews, support technical decision making and help evolve the team's development standards and ways of working.

Platform Expertise:

 * Configure and develop within experimentation platforms such as Optimizely, Adobe Target or similar technologies, supporting both client-side and server-side experimentation where appropriate.

Continuous Improvement:

 * Stay up to date with emerging CRO techniques, browser capabilities and front-end technologies, identifying opportunities to improve our experimentation capability.