Senior Front End Developer - CRO/Optimisation
Posted 2 days ago by Square One Resources
£650 Per day
Inside
Hybrid
London, UK
Summary: The Senior Front End Developer - CRO/Optimisation role involves optimizing web UI campaigns for new services and applications within a leading telecommunications company. The position requires extensive experience in front-end development and conversion rate optimization (CRO) to enhance user experience and achieve business objectives. The developer will collaborate with various teams to design and implement complex applications while utilizing optimization tools in an Agile environment. This contract role is based in London with a hybrid working arrangement, requiring up to two days per week in the office.
Key Responsibilities:
- Develop and optimize A/B/MVT campaigns for web UI.
- Collaborate with business partners, engineers, data scientists, and UX designers.
- Design, implement, test, deliver, and document complex applications and tools.
- Utilize optimization tools within an Agile squad to enhance engineering quality.
- Ensure responsive design for both desktop and mobile experiences.
Key Skills:
- Strong experience in A/B/MVT optimization campaigns.
- Excellent knowledge of Vanilla JavaScript, CSS/Sass, HTML, jQuery.
- Experience with React or Angular frameworks is advantageous.
- Technical expertise in A/B testing platforms like Optimizely or Adobe Target.
- Understanding of end-to-end user journeys and customer experience.
- Experience in website personalization and audience targeting.
- Experience in building experiments for single-page applications (SPAs).
- Advanced understanding of data analytics and tag management systems (GTM).
Salary (Rate): £650 daily
City: London
Country: UK
Working Arrangements: hybrid
IR35 Status: inside IR35
Seniority Level: Senior
Industry: IT
Job Title: Senior Front End Developer - CRO/Optimisation
Location: London - up to 2 days per week in the office (Reading, Manchester or Birmingham would also be considered)
Salary/Rate: £650 inside IR35
Start Date: 20/07/26
Company Introduction
We have an exciting opportunity now available with one of our sector-leading telecommunications clients! They are currently looking for a skilled Front End Developer with extensive CRO experience to join their team for a contract until the end of the year.
We are looking for an experienced Senior Optimisation Engineer to work in our Optimisation team to help build out the web UI campaigns for our new services and applications.
This is a role for an experienced Front End web application developer to optimise our current UI to achieve OKR's set by the business and improve our customer usage and enjoyment metrics. You will be a strong Front End coder with experience of working in experimentation, optimisation & personalisation. In this role you will be working with optimisation tools in an Agile squad, ultimately responsible for and further evolving the engineering quality, design, implementation, and operation of your product.
You will work with business partners, engineers, data scientists, and UX designers to design, implement, test, deliver, and document complex applications, tools, systems and services
The must haves:
- Strong experience developing A/B/MVT optimisation campaigns
- Excellent knowledge of Vanilla JavaScript, CSS/Sass, HTML, jQuery
- Front End development experience in either React or Angular framework could be an advantage
- Technical expertise in A/B testing platforms like Optimizely or similar such as Adobe Target etc.
- A passion for great online experience and an understanding of end-to-end user journeys and customer experience/CX
- Solid experience of website personalisation and audience targeting
- Solid experience of working with fully responsive websites and ability to deliver experiences for desktop and mobile devices
- Solid experience of working with/building experiments for SPAs
- Advanced understanding of Data analytics and Tag management systems (GTM) - integrations and custom event tracking
If you are interested in this opportunity, please apply now with your updated CV in Microsoft Word/PDF format.
Disclaimer
Notwithstanding any guidelines given to level of experience sought, we will consider candidates from outside this range if they can demonstrate the necessary competencies.
Square One is acting as both an employment agency and an employment business, and is an equal opportunities recruitment business. Square One embraces diversity and will treat everyone equally. Please see our website for our full diversity statement.