With nearly two decades of experience in web development, I specialise in crafting fast, accessible, and scalable WordPress solutions for agencies, charities, and content-heavy platforms. Up until last year, I led the WordPress practice at Manifesto, a leading UK digital agency, where I oversaw the delivery of large-scale, high-impact projects from discovery through to long-term support. I'm a hands-on developer who enjoys collaborating closely with designers and strategists to bring ideas to life through clean, thoughtful code.…

Leon Sinclair

With nearly two decades of experience in web development, I specialise in crafting fast, accessible, and scalable WordPress solutions for agencies, charities, and content-heavy platforms. Up until last year, I led the WordPress practice at Manifesto, a leading UK digital agency, where I oversaw the delivery of large-scale, high-impact projects from discovery through to long-term support. I'm a hands-on developer who enjoys collaborating closely with designers and strategists to bring ideas to life through clean, thoughtful code.…

Available to hire

With nearly two decades of experience in web development, I specialise in crafting fast, accessible, and scalable WordPress solutions for agencies, charities, and content-heavy platforms. Up until last year, I led the WordPress practice at Manifesto, a leading UK digital agency, where I oversaw the delivery of large-scale, high-impact projects from discovery through to long-term support.

I’m a hands-on developer who enjoys collaborating closely with designers and strategists to bring ideas to life through clean, thoughtful code.

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Skills

Experience Level

CSS
Expert
HTML5
Expert
JavaScript
Expert
WordPress
Expert
PHP
Expert
API
Expert

Language

English
Fluent

Work Experience

Freelance WordPress Developer at Freelance
September 1, 2024 - Present
Worked with a range of clients on various WordPress projects including developing WooCommerce shops for BBC Children in Need and TreeStory, multilingual campaign websites for End Fossil Finance, and senior development support for Wholegrain Digital amongst others.
Lead Engineer at Manifesto (part of TPXimpact)
September 30, 2024 - July 15, 2025
Built a WordPress and front-end development team, setting standards, mentoring, providing technical direction, and managing projects throughout their lifecycle. Introduced atomic design principles and rolled out Pattern Lab for delivering design systems. Played a key role in pitching work and securing major projects during the company's growth and merger phases.
Freelance full-stack web developer
January 1, 2013 - July 15, 2025
Worked mainly in the education sector, engineering custom high-quality websites using bespoke PHP CMS tailored to each client's needs.

Education

BA (Hons) degree in Digital Media at UAL London College of Communication
August 1, 2006
Grade: 2:1
BA (Hons) at UAL London College of Communication
January 1, 2006 - December 31, 2006

Qualifications

Add your qualifications or awards here.

Industry Experience

Non-Profit Organization, Education, Software & Internet, Professional Services, Retail
    paper Guy's and St Thomas' NHS Foundation Trust

    Design and build five distinct websites to represent the different organisations within the charity.

    What I Did:

    • Led the dev team while building core functionality and integrations.
    • Built a WordPress multisite for the three donor-facing charity sites, each with distinct branding (using child themes) but sharing the same underlying code (parent theme). This means features added to one site become available on all three.
    • Implemented custom API integrations for various 3rd party services.
    • Ensured website was accessible and WCAG 2.1 compliant.

    Impact:

    The multisite approach significantly reduced development time and long-term maintenance overhead while improving consistency across brands. The launch streamlined donation journeys, improved accessibility, and provided a scalable platform for future campaigns.

    paper Fauna & Flora

    Complete redesign and build of the Fauna & Flora website with the aim of boosting engagement and fundraising, while also improving digital-sustainability standards – all without compromising on visual impact.

    What I Did:

    • Led the dev team while building core functionality and integrations.
    • Implemented custom API integrations for various 3rd party services.
    • Ensured website was accessible and WCAG 2.1 compliant.
    • Migrated content from the old platform with some complex data manipulation to ensure it worked as expected in the new platform.

    Impact:

    The end result was a doubling of conversion rates and a 90% reduction in website size and page weight. The website is now more sustainable and easier to maintain.

    paper Unicef UK

    Complete redesign and build of the Unicef UK website, ensuring it supports vital fundraising efforts and increases the impact of the charity’s work.

    What I Did:

    • Led the dev team while building core functionality and integrations.
    • Rebuilt the platform in WordPress.
    • Implemented custom API integrations for various 3rd party and internal systems.
    • Ensured website was accessible and WCAG 2.1 compliant.
    • Migrated content from the old platform.

    Impact

    Conversion rates more than doubled. Unicef UK received more online donations in a single month than ever before.

    The Unicef UK website has since won several awards, including a Silver Lovie Award and People’s Lovie Award for Best Homepage, a Computing Digital Technology Leaders Award for Website Project of the Year and a Drum Network Award for Charity Campaign/Strategy of the Year.