Sentry

Sentry makes error tracking and application performance monitoring software for developers. It began around 2011 as an internal exception logging tool for Django at Disqus, built by David Cramer and Chris Jennings, was open sourced, and launched a hosted paid version around 2012. By February 2013 TechCrunch reported nearly 500 paying customers and a profitable side business. The company is headquartered in San Francisco with offices in Toronto and Vienna. Cramer was co-founder and CEO through the Series C; Milin Desai later became CEO.

Sentry ran on revenue for its first years. Accel led a $1.5 million seed in 2015. New Enterprise Associates led a $9 million Series A in June 2016 with Accel, at a post-money valuation TechCrunch reported at more than $40 million. NEA and Accel backed a $16 million Series B in May 2018, which TechCrunch later said valued the company at $100 million. Accel led a $40 million Series C in September 2019 with NEA, bringing the total to $66.5 million. In February 2021 Sentry raised a $60 million Series D at a $1 billion valuation from Accel, NEA and Bond, taking total funding to about $127 million. Sentry now states it has raised $217 million in six rounds, which implies a sixth round of roughly $90 million whose terms were not confirmed in the sources reviewed. Its website lists Accel, Bond, NEA and K5 as investors.

The company remains private. Sentry says it serves more than 200,000 organizations in 146 countries and processes more than 190 billion events a day, up from 50,000 organizations at the Series C and 68,000 at the Series D. It has grown by acquisition: Codecov, the code coverage platform, in December 2022 on undisclosed terms; the Syntax web development podcast in April 2023; and Emerge Tools, a mobile app size and testing platform, in May 2025.

Sentry illustrates a bottom up developer tool that reached product adoption before raising institutional money. Accel entered at the seed in 2015 and invested in every round after, and NEA entered at the Series A in 2016, both at valuations under $100 million. Five years later the Series D priced the company at $1 billion, up to about 25 times the Series A post-money of more than $40 million. There has been no IPO or sale, so those gains remain on paper roughly a decade after the first institutional check.