Senior CRO Developer

• Build, implement, and QA A/B and multivariate tests across client websites
• Develop high-quality front-end code using HTML, CSS, and JavaScript
• Work closely with analysts, designers, and strategists to bring test ideas to life
• Configure experiments within tools such as AB Tasty, Optimizely, VWO, or similar platforms
• Manage multiple experiments simultaneously in a fast-paced environment
• Ensure robust QA processes and maintain high technical standards
• Collaborate with stakeholders across different functions and client teams
• Contribute to best practices and support continuous improvement within the experimentation function

• Strong commercial experience in CRO development and experimentation
• Proven front-end development capability with HTML, CSS, and JavaScript
• Experience working with A/B testing or personalisation platforms such as AB Tasty, Optimizely, VWO, or similar
• Ability to manage multiple projects and stakeholders across different business areas
• Experience in agency environments or working across multiple brands or business units
• Strong problem-solving skills with attention to detail and quality
• Confident communicator able to explain technical concepts clearly

• Salary up to £60,000 depending on experience
• Hybrid working model with flexibility on office days
• Opportunity to work across a wide variety of clients and platforms
• Clear progression path with scope to develop into more senior or leadership responsibilities
• Supportive team culture focused on learning and continuous improvement

They are a specialist digital optimisation consultancy focused on improving website performance through experimentation, analytics, and SEO. The business has grown steadily in recent years and is recognised for delivering measurable improvements in conversion and user experience for its clients. With a collaborative and learning-driven culture, they prioritise innovation, development, and high-quality delivery. You will be joining a close-knit team where your work has visible impact.