CRO Developer

As a CRO Developer, you will be responsible for building, implementing, and maintaining A/B tests and experiments across a range of digital products. You will work closely with analysts, marketers, designers, and stakeholders to translate hypotheses into live experiments that drive measurable business results.

• Build and deploy A/B and multivariate tests using HTML, CSS, and JavaScript
• Develop high-quality experiment code across websites and digital platforms
• Work with CRO and product stakeholders to turn testing ideas into live experiments
• Implement personalisation and experimentation campaigns using leading CRO tools
• Ensure experiments are technically robust, performant, and accurately tracked
• Debug, troubleshoot, and optimise testing implementations
• Collaborate with analytics teams to support experiment measurement and reporting
• Contribute to experimentation best practices, processes, and governance
• Identify technical opportunities to improve customer journeys and conversion performance

• Strong commercial experience as a CRO Developer, Front End Developer, or Experimentation Developer
• Hands-on experience building and deploying experiments using HTML, CSS, and JavaScript
• Experience with CRO and experimentation platforms such as Optimizely, VWO, AB Tasty, Convert, Dynamic Yield, or similar
• Strong understanding of A/B testing methodologies and experimentation principles
• Experience working with web analytics and performance measurement tools
• Ability to write clean, efficient, and maintainable front-end code
• Understanding of customer journeys, user behaviour, and conversion optimisation
• Comfortable working closely with technical and non-technical stakeholders
• Experience within performance marketing, ecommerce, lead generation, or high traffic digital environments is beneficial

• £50,000 - £60,000 base salary
• Bonus scheme
• Hybrid working model with flexibility
• Opportunity to help shape a growing experimentation function
• Exposure to high traffic digital products and large-scale testing programmes
• Strong career progression opportunities
• Collaborative and data-driven environment

They are an established digital performance business operating across multiple international markets. Through a portfolio of proprietary digital platforms, they manage and optimise the full customer journey from acquisition through to conversion. Their data-driven approach to growth has created a strong culture of experimentation, with significant opportunities to improve customer experiences through testing. Continued expansion has led to investment in building internal CRO and experimentation capability.