Justin Duke

Justin Duke is a software engineer and founder best known for Buttondown, a minimalist email newsletter platform aimed at writers, developers and independent publishers. He started Buttondown in late 2016 as a side project while working as an engineer, and later an engineering manager, at Stripe, after earlier roles that included Amazon.

Buttondown grew slowly and steadily for years as a nights-and-weekends project. Duke has described early growth where a good month meant a single new customer, and by December 2022 the product was at roughly $15K in monthly recurring revenue. Around that time he left Stripe to work on Buttondown full time.

Since going full time he has grown Buttondown from a solo operation into a small team while keeping it self-funded and cash-flow profitable. In his 2025 year-in-review he reported 61% revenue growth, along with a long list of shipped features such as a CLI, localization, managed DNS and gift subscriptions. The product is built on a deliberately familiar stack of Django and Vue.

Duke lives in Richmond, Virginia, is a partner at the investment firm Third South Capital, and writes extensively on his personal blog, Applied Cartography, including weeknotes, book reviews and annual reviews. Over the years he has also built a series of smaller projects, including Spoonbill, which tracked changes to social media profiles.