CRO Developer — Hybrid, High-Traffic A/B Testing

Harnham; Manchester; Hybrid; GBP 34,000 - 46,000; Full time

Benefits offered by this job

Hybrid work schedule

Work on high-traffic platforms

Exposure to international markets

Ownership and autonomy

Clear progression to CRO Manager

Collaborative CRO team

Job summary

Harnham is seeking a CRO Developer in Manchester to design, build and deploy A/B tests across multiple digital products. You will work within an established CRO function, driving improvements in conversion performance and gaining hands-on experience with a mature experimentation programme.

You will deploy tests using JavaScript, HTML and CSS, and collaborate with marketing, product and development teams. The role offers hybrid work with 2–3 days in the office and opportunities to progress toward

Qualifications

• CRO experience with hands-on A/B testing.
• Experience building and deploying tests on high-traffic sites.
• Strong JavaScript, HTML and CSS skills.
• Familiarity with experimentation platforms (Convert.com/Optimizely/VWO).
• Ability to translate data into test plans.
• Understanding statistics in experimentation.
• Experience with lead generation or performance marketing is advantageous.

Responsibilities

• Build and deploy A/B and multivariate tests using JavaScript, HTML and CSS.
• Implement experiments via Convert.com and Optimizely.
• Develop test variations to improve conversions.
• Analyze results to derive actionable insights.
• Collaborate with marketing, product and development teams.
• Use behavioral data to identify optimization opportunities.
• Manage multiple experiments across digital products.
• Support ongoing CRO programme evolution.
• Improve customer journeys and conversion performance.

Skills

CRO expertise

A/B testing

JavaScript

HTML/CSS

Experimentation methodology

Data analysis

Customer behavior analysis

Test planning

High-traffic websites

Lead generation or performance mktg

Tools

Convert.com

Optimizely

VWO

Job description

Harnham is seeking a CRO Developer in Manchester to design, build and deploy A/B tests across multiple digital products. You will work within an established CRO function, driving improvements in conversion performance and gaining hands-on experience with a mature experimentation programme.

You will deploy tests using JavaScript, HTML and CSS, and collaborate with marketing, product and development teams. The role offers hybrid work with 2–3 days in the office and opportunities to progress toward