Two Engineers Sold Inbox App for Over $4 Million While Keeping Full-Time Jobs

Jordan Gaston and David Emelianov developed Trimbox, a subscription-based inbox-cleaning application, while maintaining full-time employment at separate technology companies. They sold the business at the end of 2025 for more than $4 million. The two engineers first collaborated on the project in 2020 after reconnecting from earlier acquaintance.

Gaston began the work after hearing complaints from his mother about managing email volume, and Emelianov joined after reviewing an early demo.

They spent three to four months building the initial Chrome extension version and posted it on a side-project forum, where it received significant attention. After pausing work from May to September 2021, they resumed development, added paid subscriptions, and launched mobile versions for iOS and Android in 2023 to expand advertising reach.

The company reached $232,000 in monthly recurring revenue before the sale. Gaston and Emelianov each devoted roughly 20 hours per week outside their primary jobs to marketing, customer support, and product adjustments.

Emelianov stated they copied code from the web application into ChatGPT to convert it for mobile platforms. They also trained an AI system on their help-center documentation to handle most customer-service requests, intervening only when the system escalated cases.

During the sale process, the founders used AI to run valuation simulations and prepare specific questions for legal counsel, which they said reduced time and fees. Gaston and Emelianov cited family obligations and a desire to realize value from the business as reasons for selling.

They indicated plans to develop additional applications using similar methods once they have more available time.