Xander Gottlieb, Developer in Brighton, United Kingdom
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Xander Gottlieb

Verified Expert  in Engineering

Bio

Xander is a senior front-end software engineer with expertise in developer experience and technical leadership. Recently, he's helped React teams implement design systems to boost productivity and UX, as well as interview and train new hires. Clients appreciate his ability to listen and build consensus among developers, designers, business leaders, and users alike. As a mentor, writer, and workshop leader, Xander inspires colleagues, students, and thousands of Stack Overflow and blog readers.

Portfolio

Blastoff Design
Leadership, Flutter, React, TypeScript, Tailwind CSS
Toptal
React, TypeScript, Design Systems, TanStack Table, GraphQL
WisdomAI
React, Storybook, Next.js, Figma, React Testing Library

Experience

  • User Experience (UX) - 9 years
  • React - 6 years
  • Leadership - 6 years
  • Flutter - 5 years
  • Storybook - 4 years
  • React Testing Library - 4 years
  • TypeScript - 4 years
  • Design Systems - 4 years

Availability

Full-time

Preferred Environment

Flutter, React, Next.js, TypeScript, GraphQL

The most amazing...

...thing I've developed is a suite of cross-platform mobile/web apps built with Flutter/React, showcased by Google, and commended by King Charles.

Work Experience

Founder

2018 - PRESENT
Blastoff Design
  • Invented and co-invented a suite of cross-platform mobile/web apps built with Flutter/React, showcased by Google, and commended by King Charles.
  • Collaborated with NHS healthcare providers in the UK to build Help at Hand. Worked iteratively to solve problems for both doctors and patients, all while keeping sensitive health data secure — as verified by independent pen testing.
  • Created the first version of Number Line over a weekend — in time for a maths lesson on Monday. It's now used by over 100,000+ students globally.
  • Merged natural language processing with Tinder's card-swiping interface to create Grammapp.
  • Mentored two beginner coders from zero experience to full-time jobs in software engineering and ran coding workshops for children aged 8-11.
Technologies: Leadership, Flutter, React, TypeScript, Tailwind CSS

Front-end Software Engineer

2018 - PRESENT
Toptal
  • Joined the prestigious "top 3% of freelance talent", collaborating remotely as a full-time team member with big and small companies in time zones from India to California.
  • Was promoted to a small team of React experts as part of a 2-year full-time contract with a leading data security company in Silicon Valley. Trusted to review code, conduct developer surveys, and encourage maintainable coding patterns.
  • Pulled off massive refactors reliably using codemods, making monolithic components more composable while minimizing regressions.
  • Pushed the limits of React rendering to enable cutting-edge designs without compromising performance.
Technologies: React, TypeScript, Design Systems, TanStack Table, GraphQL

Software Engineering Consultant

2024 - 2024
WisdomAI
  • Led the development of a component-driven design system in React. This accelerated new features, reduced regressions, and resulted in a simpler and more cohesive user experience.
  • Built ergonomic new data table components to support advanced filtering and customization, enabling the design team's vision while boosting developer velocity.
  • Created animations and micro-interactions with meticulous attention to detail, each with a focus on performance and frictionless user experience.
  • Worked with stakeholders across the engineering, product, and design teams to estimate schedules, prioritize new features, and save time with open source code where possible.
Technologies: React, Storybook, Next.js, Figma, React Testing Library

Software Engineering Consultant

2023 - 2024
Kavedon Kapital
  • Bootstrapped a new team of React developers, establishing best practices like continuous integration, code reviews, and a component-driven design system.
  • Improved cross-team communication by leading weekly meetings and setting up a 'single source of truth' issue tracker.
  • Led interviews and vetted candidates through self-devised coding challenges.
Technologies: React, Continuous Integration (CI), Leadership, TypeScript

Head of Web Development

2015 - 2018
Think Digitally
  • Maintained strong relationships with clients including CBRE and Ogilvy.
  • Built and maintained websites for 30+ small businesses.
  • Learned from industry experts in design and user experience.
Technologies: User Experience (UX), Page Speed Optimization, Responsive Design, React

Web Developer

2012 - 2015
Freelance
  • Improved front-end development, digital marketing, and user experience for clients from Towergate Insurance to Typhoo Tea.
  • Used animation to increase engagement, creating everything from pure-CSS parallax effects to full-on 2D physics simulations.
  • Pioneered the use of React to elevate the UX of both site visitors and admins — through WordPress's block-based Gutenberg editor.
Technologies: JavaScript, HTML, CSS, WordPress, Animation

Help at Hand

https://hand.community
A suite of mobile and web apps built in collaboration with NHS healthcare providers to reduce doctors' appointments through 'social prescribing.' I worked iteratively to solve problems for both doctors and patients, all while keeping sensitive health data secure — as verified by independent pen testing.

Stir Crazy

https://www.stircrazy.app
A deck of cards to share at a safe 2m-20,000km distance. I created and successfully monetized this cross-platform (web/Android/iOS) real-time multiplayer game during the COVID-19 pandemic, focusing on speed and beautiful animation.

Number Line

https://numberline.school
An infinitely-zoomable number line to use in the classroom. I built the first version over a weekend — in time for a maths lesson on Monday. It's now available on the web/Android/iOS and used by over 100,000+ students globally.
2015 - 2018

Bachelor of Science Degree in Computer Science with Philosophy

Durham University - Durham, UK

Libraries/APIs

React, TanStack Table, React Testing Library

Tools

Figma, Sketch

Languages

JavaScript, HTML, CSS, TypeScript, GraphQL

Frameworks

Flutter, Tailwind CSS, Jest, Next.js

Platforms

WordPress, Android, iOS, Firebase

Paradigms

Continuous Integration (CI)

Other

User Experience (UX), Page Speed Optimization, Design Systems, Storybook, Responsive Design, Leadership, Animation, Static Site Generators, Natural Language Processing (NLP)

Collaboration That Works

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