Senior Full Stack Engineer - Team Web

Fin. The highest performing Customer Agent; Greater London; Hybrid; GBP 90,000 - 140,000; Full time

Benefits offered by this job

Competitive salary and equity

Lunch provided and snack-rich office

Pension scheme & match

Health and dental insurance

Paid time off

Cycle-to-Work

MacBooks provided

Job summary

Fin is seeking a Senior Full Stack Engineer to join Team Web, crafting intuitive front-end experiences and scalable backend systems. You’ll collaborate with product marketers, designers, and engineers across the business to shape the future of our website, from UI to infrastructure, across web and mobile.

Ideal candidates have 8+ years in full stack development, expert JS/React, and experience with CI/CD, cloud infra, and analytics. This is a hybrid role in the United Kingdom.

Qualifications

• 8+ years of experience in full stack development with JavaScript, HTML, and CSS.
• Expert in front-end frameworks (React, Next.js, Tailwind).
• Experience with CMS platforms (Contentful, Sanity) and marketing tools (Google Tag Manager, Marketo).
• Experience in CI/CD tools (CircleCI) to streamline development workflows.
• Familiarity with infrastructure as code tools (Terraform) and AWS.
• Experience with A/B testing and analytics.
• Knowledge of performance optimization for fast-loading websites.
• Experience in writing tests for front-end components (Jest, Mocha, Cypress).
• Bachelor’s degree in CS/SE or related field or equivalent practical experience.

Responsibilities

• Design, build, and maintain end-to-end web solutions — from modern UIs to backend services, APIs, and infrastructure.
• Collaborate with design, brand, marketing, and content teams to deliver seamless, performant experiences across web and mobile.
• Develop backend logic and APIs, manage data flows, and integrate with third-party platforms.
• Optimize website performance and asset management.
• Set up and manage infrastructure using Vercel, AWS, CloudFront, Terraform, and CI/CD pipelines (e.g., CircleCI).
• Implement and maintain web analytics, and support A/B testing for data-driven decisions.
• Stay current with emerging technologies and trends to improve development processes and UX.
• Be comfortable writing backend software end to end.
• Build using AI-powered developer tools to remove friction and solve meaningful problems.

Skills

JavaScript

React

Next.js

Tailwind

CMS Contentful

Google Tag Manager

Marketo

CircleCI

Terraform

AWS

A/B testing

Testing: Jest

Testing: Mocha

Testing: Cypress

CI/CD

Education

Bachelor's degree in Computer Science/Software Engineering or related field

Tools

Vercel

CloudFront

S3

Terraform

CircleCI

Job description

Fin is the AI Customer Agent company on a mission to help businesses provide perfect customer experiences.

Our AI Agent Fin is the highest-performing AI Customer Agent on the market today, enabling businesses to deliver impeccable, always-on customer support across the customer journey – from service, to sales, to ecommerce. Powered by our own AI models, Fin resolves complex customer issues end-to-end across every channel, with minimal set-up and integration. Fin can also be combined with our natively integrated Intercom help desk for one single system that is designed to meet the needs of modern day support teams.

Founded in 2011, Fin became one of the fastest growing companies and remains one of the largest private software companies in the world with nearly 30,000 global businesses using our products to transform their customer support. Driven by our core values, we push boundaries, build with speed and intensity, and relentlessly deliver incredible value to our customers.

What's the opportunity?

Our company website is the centerpiece of our brand — the public source of truth about Fin's products and the number one driver of leads for our demand generation team. Fin.ai sits at the intersection of awareness, product marketing, demand, and support, requiring robust, performant, and reliable infrastructure as much as polished user-facing interfaces.

We’re looking for a Senior Full Stack Engineer to join Team Web, who is passionate about crafting intuitive front-end experiences and building the backend systems and tools that power them. You’ll play a key role in shaping the future of our website across the full stack, from UI to infrastructure, while collaborating with product marketers, designers, and engineers across the business.

See the teams most recent work here

What will I be doing?

• Design, build, and maintain end-to-end web solutions — from modern UIs to backend services, APIs, and infrastructure.
• Collaborate with design, brand, marketing, and content teams to deliver seamless, performant experiences across web and mobile.
• Develop backend logic and APIs, manage data flows, and implement systems that integrate with third-party platforms.
• Optimize website performance by applying best practices in front-end development, including lazy loading, and efficient asset management.
• Set up and manage infrastructure using tools like Vercel, AWS, Cloudfront, Terraform, and CI/CD pipelines (e.g., CircleCI).
• Implement and maintain web analytics, and support A/B testing for data-driven decisions.
• Stay current with emerging technologies and trends to continually improve our development processes and user experience.
• Be comfortable writing backend software. We look for engineers to be able to unblock themselves end to end
• Build using the best tools in the industry. We invest heavily in AI-powered developer tools that remove friction and help you focus on solving meaningful problems.

What skills do I need?

• 8+ years of experience in full stack development, with expertise in JavaScript, HTML, and CSS.
• Expert in front-end frameworks such as React, Next.js, Tailwind.
• Experience in CMS platforms (such as Contentful and Sanity) and marketing tools (e.g. Google Tag Manager, Marketo)
• Experience in CI/CD tools (such as CircleCI) to streamline and automate development workflows.
• Familiarity with infrastructure as code tools such as Terraform, and cloud platforms like AWS (Vercel, CloudFront, S3, etc.).
• Experience with A/B testing and familiarity with analytics tools to drive data-informed design and development decisions.
• Knowledge of performance optimization techniques and best practices for fast-loading, responsive websites.
• Experience in writing tests for front-end components, with familiarity in testing frameworks (e.g., Jest, Mocha, Cypress)
• Strong problem-solving skills and the ability to work independently and as part of a team.
• Bachelor’s degree in Computer Science, Software Engineering, or a related field (or equivalent practical experience).

Benefits

We are a well treated bunch, with awesome benefits! If there’s something important to you that’s not on this list, talk to us!

• Competitive salary and equity in a fast-growing start-up
• We serve lunch every weekday, plus a variety of snack foods and a fully stocked kitchen
• Regular compensation reviews - we reward great work!
• Pension scheme & match up to 4%
• Peace of mind with life assurance, as well as comprehensive health and dental insurance for you and your dependents
• Flexible paid time off policy
• Paid maternity leave, as well as 6 weeks paternity leave for fathers, to let you spend valuable time with your loved ones
• If you’re cycling, we’ve got you covered on the Cycle-to-Work Scheme. With secure bike storage too
• MacBooks are our standard, but we also offer Windows for certain roles when needed.

#LI-Hybrid

At Fin, we want to give people what they need to do the best work of their careers. Our benefits and programs are designed to support your health and wellbeing, your family, your time away from work, and your financial future. Offerings vary by location in line with local practices and requirements.
Learn more about working at Fin and the benefits we offer at fin.ai/careers.

Policies

Fin has a hybrid working policy. We believe that working in person helps us stay connected, collaborate easier and create a great culture while still providing flexibility to work from home. We expect employees to be in the office at least three days per week.

We have a radically open and accepting culture at Fin. We avoid spending time on divisive subjects to foster a safe and cohesive work environment for everyone. As an organization, our policy is to not advocate on behalf of the company or our employees on any social or political topics out of our internal or external communications. We respect personal opinion and expression on these topics on personal social platforms on personal time, and do not challenge or confront anyone for their views on non-work related topics. Our goal is to focus on doing incredible work to achieve our goals and unite the company through our core values.

Fin values diversity and is committed to a policy of Equal Employment Opportunity. Fin will not discriminate against an applicant or employee on the basis of race, color, religion, creed, national origin, ancestry, sex, gender, age, physical or mental disability, veteran or military status, genetic information, sexual orientation, gender identity, gender expression, marital status, or any other legally recognized protected basis under federal, state, or local law.