David Smalley

David Smalley is a Leeds University graduate and tech entrepreneur who co-founded Litmus in 2005 with two school friends, Paul Farnell and Matt Brindley. What started as a bootstrapped venture—funded with just a £10,000 bank loan—grew into the world's leading email testing and optimisation SaaS platform, integrated with major email service providers including Salesforce, Adobe, and HubSpot.

A self-taught Ruby developer, David built the original customer-facing part of the product himself before the company scaled. Litmus eventually grew to over 150 employees across offices in Boston, London, and San Francisco, serving major global brands including 9 of the top 10 ecommerce companies and 23 of the top 25 US advertising agencies.

In 2015, the company attracted $49 million in growth equity from Spectrum Equity. In April 2025, Litmus was acquired by Validity, bringing David's 20-year journey with the company to a successful conclusion.

After stepping back from day-to-day operations in 2018, David completed an MBA at Alliance Manchester Business School and focused on supporting the next generation of entrepreneurs. He has mentored startups through TechStars and Connect Yorkshire, drawing on his experience of scaling a bootstrapped company into a global enterprise—much of it with a remote-first workforce. Based in Harrogate with his wife and two daughters, David is also a qualified private pilot and a keen photographer.