Tammie
Siew

The Instagram bio says "janitor at @pbd.vc." The fund size says $125 million. Tammie Siew occupies that contradiction comfortably - which is partly why she's any good at what she does.

Pebblebed, the deep tech venture firm she co-founded in 2022, backs what Siew calls "the foundational layers of progress." In practice, that means developer platforms that accelerate how software gets built, robot operating systems, AI simulation engines, and formal verification systems. The category most VCs race past on the way to the application layer.

The logic is precise and a little contrarian: if you own the substrate, you don't need to predict which application wins. You just need to be right that applications will proliferate. And on that point, Siew is very willing to bet.

She describes Pebblebed's target as "self-protecting ideas" - the kind that are simple to state, punishing to replicate, and valuable precisely because most investors hear them and move on. Getting to a company like that before the herd shows up requires being able to recognize technical depth before it has traction. That's a different muscle than pattern-matching on founders or markets. It's the muscle she has been building for a decade across two continents and three roles.

Siew grew up in Singapore, won a Humanities Scholarship at Hwa Chong Institution, and went to Cornell on the back of that academic foundation - studying Economics and English Literature simultaneously, finishing with Distinction in All Subjects. The combination is not incidental. Economic frameworks and close reading are both, at their core, about finding what a thing actually means versus what it appears to say.

She graduated into management consulting - PwC, then BCG, covering fintech incubation, eSports strategy, sales infrastructure. The analyst's training, the structured decomposition of problems, still shows up in how she writes and how she talks about companies. But it was a detour, not a destination.