Front-end engineer with 6+ years' experience building consumer-facing products and design systems, most recently at Cleo, a consumer fintech app. Experience owning features from proof-of-concept through cross-functional delivery to production rollout, with a strong focus on component library architecture, design tokens, and developer tooling. Now moving into freelance front-end and design-systems contracting.

Sophia Barclay

Front-end engineer with 6+ years' experience building consumer-facing products and design systems, most recently at Cleo, a consumer fintech app. Experience owning features from proof-of-concept through cross-functional delivery to production rollout, with a strong focus on component library architecture, design tokens, and developer tooling. Now moving into freelance front-end and design-systems contracting.

Available to hire

Front-end engineer with 6+ years’ experience building consumer-facing products and design systems, most recently at Cleo, a consumer fintech app. Experience owning features from proof-of-concept through cross-functional delivery to production rollout, with a strong focus on component library architecture, design tokens, and developer tooling. Now moving into freelance front-end and design-systems contracting.

See more

Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
See more

Language

English
Fluent

Work Experience

Front-End Engineer at Cleo
November 1, 2023 - August 1, 2026
Owned and shipped a company-wide app navigation redesign following Apple-style “Liquid Glass,” moving from proof of concept to production via reusable wrapper components and coordinating native QA before rollout at iOS 26+ scale. Built end-to-end card fraud and dispute experiences across customer journeys (dispute creation, evidence submission, and replacement card flow) and an internal operations console with SLA tracking, filtering, sorting, and CSV export. Delivered personalized eligibility transparency experiences and supported data-informed product decisions via A/B testing across funnels; contributed to the design systems platform by maintaining shared components and leading token migrations from legacy to design-system schemas. Authored custom ESLint rules to enforce design-system conventions and shift quality enforcement into CI. Packaged the in-app component library into a standalone, semvered, CI-published design system with zero product logic in the package, improving po
Software Engineer at Cazoo
December 1, 2022 - November 1, 2023
Led development of front-end features from ideation through design, implementation, and deployment for Cazoo financing products, using A/B test results to iterate product design and align UX with user habits. Built scalable tooling for internal inventory management while working closely with commercial teams to tailor the platform to business requirements. Repurposed Cazana products to create Cazoo Data Services including a full refactor and rebrand of an existing codebase. Conducted code reviews to maintain quality, documented code-related issues and technical debt, and championed adoption of an internal Storybook UI library with best practices and contribution guidelines.
Associate Software Engineer at Cazoo
October 1, 2021 - December 1, 2022
Supported front-end development for finance-related products, contributing to scalable features and iterative UX improvements. Collaborated with cross-functional stakeholders and ensured quality through development, testing, and deployment practices.
Front-End Developer at Cazana
August 1, 2020 - October 1, 2021
Developed Cazana B2B SaaS products within a small cross-functional team, collaborating on the core vehicle data visualisation product, Experian Auto Check, and client admin panel. Prioritized responsive web design, web accessibility, and cross-browser compatibility.
Front-End Developer at TUI Media
October 1, 2019 - June 1, 2020
Developed interactive web applications and supporting content management systems for clients across the financial, energy, and media sectors, including EY and BP. Participated in full product lifecycle activities from kickoff and design sessions through user testing, sign-off, and error management; worked closely with designers to ensure pixel-perfect, well-functioning builds.
Junior Front-End Developer at TUI Media
February 1, 2019 - September 1, 2019
Built interactive web applications and content management system components as part of client projects, contributing to responsive, accessible, cross-browser experiences.

Education

MA (Hons) Chinese at University of Edinburgh
January 1, 2011 - January 1, 2015
Chinese (year abroad) at Peking University
January 1, 2013 - January 1, 2014
A-Levels at Downe House School
January 11, 2030 - September 3, 2026

Qualifications

AWS Certified Cloud Practitioner
January 1, 2021 - September 3, 2026
General Assembly, Web Development Immersive (12-week bootcamp)
January 1, 2018 - January 1, 2019

Industry Experience

Software & Internet, Financial Services

Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
See more

Hire a Front-End Developer

We have the best front-end developer experts on Twine. Hire a front-end developer in London today.