Will Lehmann / Step Function

Will Lehmann is the Founder of Step Function, a $12M fund backing technical founders building infrastructure software.

Will’s background is at Bain Capital Ventures, where he spent years cutting his teeth on enterprise software deals. Now he’s charting his own course with a fund that’s small by design, early on purpose, and built to back edge cases before they become power laws.

Most managers who spin out of multistage platforms make the same mistake. They raise big because they can, then wonder why the quality of founders drops off. Those founders were there for the brand, not the individual GP. Will is betting on something more durable: being the right size to matter.

Our conversation gets into why $250k is the sweet spot for his strategy. “It’s meaningful to the founders, and small enough that you can be collaborative. The support of a multistage investor but with the look and feel of a super angel.”

Step Function focuses on developer tools, data infrastructure, AI infrastructure, security, monitoring, observability. Will sees two forces at work that most miss. First, the density of power law outcomes. “I struggle to think of any other area of software where you so reliably get multiple multi-billion dollar outcomes every year.” Second, the practitioner’s advantage. Infrastructure software attracts founders who are users first, builders second. They’ve lived the pain, understand the gaps, and have prescriptive points of view on what needs to exist.

We also talk about why he left the comfort of a large fund. Dedicated IR team, teammates, institutional support. But he’s betting that being small, nimble, and specialized gives him the best shot at delivering returns. “Incremental improvements at the infrastructure layer create step function changes at the application layer.”

Full episode below, or on Spotify / Apple Podcasts