Late last year, Lattice CEO Jack Altman started an unusual side gig for a startup founder: He raised $20 million from investors for a venture capital fund he was launching while continuing to run Lattice, the developer of human resource management software he co-founded six years ago.

Altman’s feat reflects a new trend in startup investing. Some founders are taking on the additional role of venture capitalists, investing money from financial institutions and wealthy individuals at the same time they are guiding their own companies through critical growth periods. These include Zach Perret, CEO and co-founder of banking technology startup Plaid, and Josh Browder, founder of startup DoNotPay, as well as Altman.

Armed with fresh capital, some founders are even beginning to lead investment rounds for young startups through their venture funds, a role that reflects the larger size of their investments. They are adding to the ranks of nontraditional investors, including hedge funds and solo venture capitalists, who are increasingly competing with established VC firms for stakes in the next generation of technology startups.