Writing from the firm Updated · Q1 2026

Notes from the orchard.

We publish less than most funds, and we mean what we publish. Thesis updates, field notes from portfolio companies, occasional partner letters. No newsletter dressed up as insight.

38
Essays · since 2019
~4/qtr
Publication cadence
11k
Subscribers
2026 · 03 · 14
A patient season.
Partner letter to LPs on what the deceleration of frontier-model launches has done for the rest of the AI stack, and why we are leaning further into infrastructure.
Partner Letter E. Hartmann 9 min read
2026 · 02 · 22
Local inference, and the limits of cloud sovereignty.
Thesis update on why local-first inference will be the single most important infrastructure layer of the next five years, and where we are deploying.
Thesis Update M. Chen 14 min read
2026 · 01 · 31
A week in a closed-loop geothermal field office.
Field notes from spending five days at one of our portfolio company's pilot wells. What is harder than we expected. What is easier. What's still a fundraising story rather than a fact.
Field Notes D. Park 11 min read
2026 · 01 · 12
The boring, beautiful math of long-duration storage.
Public version of our internal memo on iron-air vs. flow chemistries. Where the cost curves actually intersect with utility procurement.
Memo D. Park 22 min read
2025 · 12 · 28
Year-end note: what we got wrong.
Our annual public ledger of the bets we passed on that we shouldn't have, and the ones we made that we wouldn't make again.
Partner Letter Partnership 16 min read
2025 · 11 · 18
Senotherapeutics, regulators, and the patience cliff.
Where the science is, what the FDA is signaling, and how we are pricing companies whose payoff is fundamentally a ten-year clinical timeline.
Thesis Update S. Okonjo 18 min read
2025 · 10 · 09
Three hours with a tactile-sensing prototype.
Two of us spent a morning trying to convince a robot to fold a t-shirt. The robot won, eventually. The lessons were about us.
Field Notes M. Chen 7 min read
2025 · 09 · 04
What good evaluation infrastructure actually looks like.
Published version of the spec we use to diligence companies in the LLM evaluation space. Why "vibes-based eval" is the standard, and what would replace it.
Memo M. Chen 19 min read
2025 · 07 · 21
Reproductive longevity is the most under-priced category we cover.
Thesis update on egg-freezing, ovarian aging, and why the medicine has run ten years ahead of the consumer product.
Thesis Update S. Okonjo 15 min read
2025 · 06 · 02
Notes on hiring your first VP of Engineering, from twelve who did it.
A practical document for portfolio CEOs entering the first executive-hire window. What worked, what failed, what nobody told them in advance.
Field Notes R. Bauer 13 min read
2025 · 05 · 14
Mid-year letter: the case for staying out of late stage.
Partner letter on the public-market repricing and why we have continued to pass on growth-stage rounds where the math no longer works for our timeline.
Partner Letter E. Hartmann 11 min read
2025 · 04 · 03
A reading list for the climate-curious investor.
The seventeen papers, three books, and four newsletters we ask new climate diligence advisors to read before joining a call.
Memo D. Park 6 min read
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