Commsor, a two-year-old startup that sells software to help companies track user engagement, is raising $50 million at a $450 million valuation, a price that includes the investment, said two people with direct knowledge of the matter. London-based Atomico is leading the round, the people added. The valuation is nearly three times higher than Commsor’s Series A round nine months ago.

The pace of financing reflects rising investor interest in community tools startups, providers of software that track customers’ level of interaction with content such as newsletters and social media. Venture capital funding has flowed into the startups even if their products are still largely unproven. New York–based Commsor has introduced a version of its software to some customers but has not released its product to the general public, according to its website.