It must be a crazy place to work at right now at OpenAI. From a human resources and political standpoint there is just so much going on.
The first thing to know about OpenAI is how quickly it's grown. When I joined, the company was a little over 1,000 people. One year later, it is over 3,000 and I was in the top 30% by tenure. Nearly everyone in leadership is doing a drastically different job than they were ~2-3 years ago.
An unusual part of OpenAI is that everything, and I mean everything, runs on Slack. There is no email. I maybe received ~10 emails in my entire time there. If you aren't organized, you will find this incredibly distracting. If you curate your channels and notifications, you can make it pretty workable.
Leadership is quite visible and heavily involved. This might be obvious at a company such as OpenAI, but every exec seemed quite dialed in. You'd see gdb, sama, kw, mark, dane, et al chime in regularly on Slack. There are no absentee leaders.
OpenAI uses a giant monorepo which is ~mostly Python (though there is a growing set of Rust services and a handful of Golang services sprinkled in for things like network proxies). This creates a lot of strange-looking code because there are so many ways you can write Python. You will encounter both libraries designed for scale from 10y Google veterans as well as throwaway Jupyter notebooks from newly-minted PhDs. Pretty much everything operates around FastAPI to create APIs and Pydantic for validation. But there aren't style guides enforced writ-large.
OpenAI runs everything on Azure. What's funny about this is there are exactly three services that I would consider trustworthy: Azure Kubernetes Service, CosmosDB (Azure's document storage), and BlobStore. There's no true equivalents of Dynamo, Spanner, Bigtable, Bigquery Kinesis or Aurora. It's a bit rarer to think a lot in auto-scaling units. The IAM implementations tend to be way more limited than what you might get from an AWS. And there's a strong bias to implement in-house.
The Codex sprint was probably the hardest I've worked in nearly a decade. Most nights were up until 11 or midnight. Waking up to a newborn at 5:30 every morning. Heading to the office again at 7a. Working most weekends. We all pushed hard as a team, because every week counted. It reminded me of being back at YC.
There's lots of really interesting nuggets in there.
Note: this piece is also a great advertosment for Codex. I really want to give it another go. Maybe I use the GUI this time rather than the CLI.