Biglight on cord

Biglight

Lead CRO Developer

External position
London, UK
Hiring internally for Biglight?
Design
Experience Design for Business Growth
Posted
6 days ago
Checked
cord regularly checks that external positions are still open
17 hours ago

Skills & Experience

Job roles: Front End
Experience level: Lead
Core skills considered: A/B Testing, Optimizely, JavaScript
Other skills considered: HTML/CSS, React, Tealium

Logistics

Base salary: Undisclosed
Some companies on cord are unable to disclose salaries publicly due to internal company policies. Message the company for salary information.
Employment type: Permanent
Remote working: Hybrid (up to 3 remote days p/w)
Visa sponsorship: Not available

Job Description

We are looking for a highly experienced, hands-on Lead CRO Developer to build and deliver A/B and multivariate experiments across our client accounts. This is fundamentally a development role. The majority of the role is hands-on coding, implementation, QA and troubleshooting of experiments, not CRO strategy, programme management, or roadmap ownership.

You will take test designs and specifications and turn them into robust, production-ready experiments across enterprise experimentation platforms. As the lead developer, you will also act as the technical escalation point for complex builds and help maintain high development and QA standards, while remaining deeply hands-on day to day.


What you will be doing

  • Build A/B and multivariate experiments from supplied concepts, designs and test specifications.
  • Write clean, robust JavaScript (ES6+), HTML5 and CSS3 to create experiment variations and functionality.
  • Develop experiments within Optimizely and other enterprise testing platforms including VWO, AB Tasty, Convert, Monetate and similar tools.
  • Build experiments within modern React and Next.js environments, including single-page applications and dynamically rendered experiences.
  • Handle technically complex tests involving DOM manipulation, application state, targeting, customer journeys and dynamic content.
  • Where appropriate, develop or support full-stack / server-side and feature experiments using SDKs, APIs and feature flags.
  • Implement and validate experiment tracking, events and data-layer requirements using tools such as GTM and Tealium.
  • Debug failed or inconsistent experiments, resolve conflicts with client codebases and troubleshoot platform or implementation issues.
  • Identify performance issues such as flicker, race conditions or unnecessary page impact and implement appropriate solutions.
  • Work directly with client developers where access to the underlying application, APIs, SDKs or data layer is required.
  • Review particularly complex experiment builds and provide technical support to other CRO developers when needed.

Essential technical skills

  • JavaScript: Advanced JavaScript (ES6+) skills. You must be comfortable writing substantial custom code for experiments rather than relying on visual editors.
  • HTML & CSS: Strong HTML5 and CSS3 development skills, including responsive implementation and accurate translation of supplied designs.
  • Optimizely: Strong hands-on experience building experiments in Optimizely Web. Experience with Optimizely Full Stack / Feature Experimentation is highly valuable.
  • Experimentation development: Extensive experience personally building and shipping A/B and multivariate tests in live ecommerce or enterprise environments.
  • React / Next.js: Strong experience developing and debugging experiments on React and Next.js applications, including SPAs.
  • QA & debugging: Excellent browser developer-tools skills, troubleshooting ability and rigorous cross-browser/device experiment QA.
  • Tracking & tag management: Experience with GTM and/or Tealium, event tracking and data layers as they relate to experimentation.
  • Cross-platform delivery: Ability to work confidently across different CMSs, ecommerce platforms, and proprietary client technology stacks.

Experimentation platforms

  • Optimizely Web
  • Optimizely Full Stack / Feature Experimentation
  • VWO
  • AB Tasty
  • Convert
  • Monetate
  • Webtrends Optimize or equivalent enterprise experimentation platforms

Highly desirable

  • TypeScript.
  • Node.js.
  • Server-side / full-stack experimentation.
  • Experimentation SDK and API implementation.
  • Feature flags and server-side decisioning.
  • Experience resolving flicker / FOOC and experiment performance issues.
  • GA4 implementation knowledge.
  • High-traffic retail and ecommerce experience.
  • Agency experience working across several client codebases and experiment pipelines at the same time.

What 'Lead' means in this role

You will not be expected to own the CRO roadmap, hypothesis strategy, or wider department. 'Lead' reflects the level of technical capability we need: someone who can take on the most complex experiment builds, make sound implementation decisions, solve difficult development problems, review code where required and act as the technical point of escalation for CRO development.


The person we are looking for:

  • A genuinely hands-on developer who enjoys building experiments and wants to remain close to the code.
  • Senior enough to work independently and take ownership of technically difficult builds.
  • Experienced in high-volume experimentation environments and able to move quickly without compromising quality.
  • Comfortable receiving a design/specification and determining how best to implement it technically.
  • Able to explain technical constraints and solutions clearly to UX, CRO, account and client development teams.
  • Pragmatic, detail-oriented, and strong at debugging.
  • Comfortable working across multiple client accounts and technology stacks.
  • Experience of working with multi-disciplinary teams and communicating with them daily to update on progress.
  • Advanced knowledge in Vanilla Javascript.
  • Experience in A/B testing and A/B testing tools.
  • Advanced knowledge of HTML/CSS.
  • Advanced knowledge of CSS-Preprocessors (e.g. SCSS).
  • Experience in cross-browser/device testing and ensuring consistency across them all.
  • Understand REST APIs and AJAX.
  • Understand of GIT version control.

Nice to have, but not essential

  • Experience with JIRA.
  • Node.js basics would be nice to have.

Company Benefits

  • Competitive salary
  • Contributory Pension Scheme
  • Access to Perkbox benefits and rewards platform, which provides a range of discounts on big retail brands and gym memberships, provides health & wellness support and free coffees!
  • Regular company wide meetings and social events
  • Access to a co-working and private office space in central London with an onsite barista, plenty of collaboration space and the chance to spend time with your colleagues face to face in a creative environment.
  • Opportunities for professional growth and career development
  • 25 days annual leave
  • Being part of a dynamic, fast-paced agency environment
  • Working with a team of incredibly talented professional colleagues
Lead CRO Developer at Biglight
Position posted 6 days ago

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Starling Bank on cord

Starling Bank

Full Stack Engineer (ML Ops)

London, UK
FinTech · Banking · Finance
A better bank for everyone
Active
over 6 months ago
Responds to
0% of requests
Responds in
1h 55m
Requests
7 pending

Skills & Experience

Job roles: Full Stack
Experience level: Mid, Senior
Core skills considered: Java, React, Redux, AWS, JavaScript

Logistics

Base salary: £70K - £110K
Employment type: Permanent
Remote working: Hybrid (up to 2 remote days p/w)
Visa sponsorship: Not available

Job Description

Starling is the UK’s first and leading digital bank on a mission to fix banking! Our vision is fast technology, fair service, and honest values. All at the tap of a phone, all the time.

Starling is the UK’s first and leading digital bank on a mission to fix banking! We built a new kind of bank because we knew technology had the power to help people save, spend and manage their money in a new and transformative way.

We’re a fully licensed UK bank with the culture and spirit of a fast-moving, disruptive tech company. We’re a bank, but better: fairer, easier to use and designed to demystify money for everyone. We employ more than 3,000 people across our London, Southampton, Cardiff and Manchester offices.

Our technologists are at the very heart of Starling and enjoy working in a fast-paced environment that is all about building things, creating new stuff, and disruptive technology that keeps us on the cutting edge of fintech. We operate a flat structure to empower you to make decisions regardless of what your primary responsibilities may be, innovation and collaboration will be at the core of everything you do. Help is never far away in our open culture, you will find support in your team and from across the business, we are in this together!

The way to thrive and shine within Starling is to be a self-driven individual and be able to take full ownership of everything around you: From building things, designing, discovering, to sharing knowledge with your colleagues and making sure all processes are efficient and productive to deliver the best possible results for our customers. Our purpose is underpinned by five Starling values: Listen, Keep It Simple, Do The Right Thing, Own It, and Aim For Greatness.

Hybrid Working

We have a Hybrid approach to working here at Starling - our preference is that you're located within a commutable distance of one of our offices so that we're able to interact and collaborate in person. We don't like to mandate how much you visit the office and work from home, that's to be agreed upon between you and your manager.

Our Data Environment

Our Data teams are excited about the value of data within the business, powers our product decisions to improve things for our customers and enhance effective and agile decision making, regardless of what their primary tech stack may be. Hear from the team in our latest blogs or our case studies with Women in Tech.

We are looking for talented data professionals at all levels to join the team. We value people being engaged and caring about customers, caring about the code they write and the contribution they make to Starling. People with a broad ability to apply themselves to a multitude of problems and challenges, who can work across teams do great things here at Starling, to continue changing banking for good.

Requirements

We have built our entire banking platform in house and mostly in Java. We are looking for people who want to work on building the tooling that is used by our engineers on a daily basis.

We are looking for people who are truly full stack, and are as comfortable polishing their javascript front end as they are debugging the innards of their java applications database interactions, or standing up infrastructure with terraform. We are looking for people who can:

  • Design REST apis.
  • Code backend services, ideally using Java, or another other server side compiled language.
  • Develop modern front ends, ideally using React and Redux.
  • Get their code into the cloud and support it there, ideally on AWS.
  • Believe in clean coding, simple solutions, automated testing and continuous deployment.
  • Like to take ownership of a feature from the original idea through to live.
  • Think (like us) that a small number of empowered developers is the right way to deliver software.

Company Benefits

  • 33 days holiday (including flexible bank holidays)
  • An extra day’s holiday for your birthday
  • 16 hours paid volunteering time a year
  • Part-time and/or flexible hours available for most roles
  • Salary sacrifice, company enhanced pension scheme
  • Life insurance at 4x your salary
  • Hybrid/remote working
  • Private Medical Insurance with VitalityHealth including mental health support and cancer care. Partner benefits include discounts with Waitrose, Mr&Mrs Smith and Peloton
  • Generous family-friendly policies
  • Varied social groups set up and run by our employees
  • Perkbox membership giving access to retail discounts, a wellness platform for physical and mental health, and weekly free and boosted perks
  • Access to initiatives like Cycle to Work, Salary Sacrificed Gym partnerships and Electric Vehicle (EV) leasing

Full details are available on our careers site

Interview Process

Interviewing is a two way process and we want you to have the time and opportunity to get to know us, as much as we are getting to know you! Our interviews are conversational and we want to get the best from you, so come with questions and be curious. In general you can expect the below, following a chat with one of our Talent Team:

  • Stage 1 - 30 mins with one of the team
  • Stage 2 - Take home challenge
  • Stage 3 - 90 mins technical interview with two team members
  • Stage 3 - 45 min final with an executive and a member of the people team
Alex Yeates on cord
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