Today we go over how hydration errors happen in react-router and how to fix them.

Imagine we have a list of paths to Parquet files on R2. We need to fetch Parquet footer of each file. However, we don’t know in advance whether we will need footers of all files and we want to avoid fetching extra. Rust has a streams abstraction. It is kind of like an iterator, but with async operations permitted. Like iterators, streams are lazy - they don’t do anything unless explicitly polled. This sounds like it ticks all the boxes, so lets try to implement it:

Watch now (20 mins) | Learn how to inspect registers, step through instructions, and investigate crashes using GDB.

A clip from “Buy Now! The Shopping Conspiracy” features a former executive of an online retailer explaining how motivated they were to make buying easy. Like, incredibly easy. So easy, in fact, that their goal was to “reduce your time to think a little bit more critically about a purchase you thought you wanted to make.” Why? Because if you pause for even a moment, you might realize you don’t actually want whatever you’re about to buy. Been there. Ready to buy something and the slightest inconvenience surfaces — like when I can’t remember the precise order of my credit card’s CCV number and realize I’ll have to find my credit card and look it up — and that’s enough for me to say, “Wait a second, do I actually want to move my slug of a body and find my credit card? Nah.” That feels like the socials too. The algorithms. The endless feeds. The social interfaces. All engineered to make you think less about what you’re consuming, to think less critically about reacting or responding or engaging. Don’t think, just scroll. Don’t think, just like. Don’t think, just repost. And now with AI don’t think at all.[1] Because if you have to think, that’s friction. Friction is an engagement killer on content, especially the low-grade stuff. Friction makes people ask, “Is this really worth my time?” Maybe we need a little more friction in the world. More things that merit our time. Less things that don’t. It’s kind of ironic how the things we need present so much friction in our lives (like getting healthcare) while the things we don’t need that siphon money from our pockets (like online gambling[2]) present so little friction you could almost inadvertently slip right into them. It’s as if The Good Things™️ in life are full of friction while the hollow ones are frictionless. Nicholas Carr said, “The endless labor of self-expression cries out for the efficiency of automation.” Why think when you can prompt a probability machine to stitch together a facade of thinking for you? ⏎ John Oliver did a segment on sports betting if you want to feel sad. ⏎ Email · Mastodon · Bluesky

Today’s my last day at Carta, where I got the chance to serve as their CTO for the past two years. I’ve learned so much working there, and I wanted to end my chapter there by collecting my thoughts on what I learned. (I am heading somewhere, and will share news in a week or two after firming up the communication plan with my new team there.) The most important things I learned at Carta were: Working in the details – if you took a critical lens towards my historical leadership style, I think the biggest issue you’d point at is my being too comfortable operating at a high level of abstraction. Utilizing the expertise of others to fill in your gaps is a valuable skill, but–like any single approach–it’s limiting when utilized too frequently. One of the strengths of Carta’s “house leadership style” is expecting leaders to go deep into the details to get informed and push pace. What I practiced there turned into the pieces on strategy testing and developing domain expertise. Refining my approach to engineering strategy – over the past 18 months, I’ve written a book on engineering strategy (posts are all in #eng-strategy-book), with initial chapters coming available for early release with O’Reilly next month. Fingers crossed, the book will be released in approximately October. Coming into Carta, I already had much of my core thesis about how to do engineering strategy, but Carta gave me a number of complex projects to practice on, and excellent people to practice with: thank you to Dan, Shawna and Vogl in particular! More on this project in the next few weeks. Extract the kernel – everywhere I’ve ever worked, teams have struggled understanding executives. In every case, the executives could be clearer, but it’s not particularly interesting to frame these problems as something the executives need to fix. Sure, that’s true they could communicate better, but that framing makes you powerless, when you have a great deal of power to understand confusing communication. After all, even good communicators communicate poorly sometimes. Meaningfully adopting LLMs – a year ago I wrote up notes on adopting LLMs in your products, based on what we’d learned so far. Since then, we’ve learned a lot more, and LLMs themselves have significantly improved. Carta has been using LLMs in real, business-impacting workflows for over a year. That’s continuing to expand into solving more complex internal workflows, and even more interestingly into creating net-new product capabilities that ought to roll out more widely in the next few months (currently released to small beta groups). This is the first major technology transition that I’ve experienced in a senior leadership role (since I was earlier in my career when mobile internet transitioned from novelty to commodity). The immense pressure to adopt faster, combined with the immense uncertainty if it’s a meaningful change or a brief blip was a lot of fun, and was the inspiration for this strategy document around LLM adoption. Multi-dimensional tradeoffs – a phrase that Henry Ward uses frequent is that “everyone’s right, just at a different altitude.” That idea resonates with me, and meshes well with the ideas of multi-dimensional tradeoffs and layers of context that I find improve decision making for folks in roles that require making numerous, complex decisions. Working at Carta, these ideas formalized from something I intuited into something I could explain clearly. Navigators – I think our most successful engineering strategy at Carta was rolling out the Navigator program, which ensured senior-most engineers had context and direct representation, rather than relying exclusively on indirect representation via engineering management. Carta’s engineering managers are excellent, but there’s always something lost as discussions extend across layers. The Navigator program probably isn’t a perfect fit for particularly small companies, but I think any company with more than 100-150 engineers would benefit from something along these lines. How to create software quality – I’ve evolved my thinking about software quality quite a bit over time, but Carta was particularly helpful in distinguishing why some pieces of software are so hard to build despite having little-to-no scale from a data or concurrency perspective. These systems, which I label as “high essential complexity”, deserve more credit for their complexity, even if they have little in the way of complexity from infrastructure scaling. Shaping eng org costs – a few years ago, I wrote about my mental model for managing infrastructure costs. At Carta, I got to refine my thinking about engineering salary costs, with most of those ideas getting incorporated in the Navigating Private Equity ownership strategy, and the eng org seniority mix model. The three biggest levers are (1) “N-1 backfills”, (2) requiring a business rationale for promotions into senior-most levels, and (3) shifting hiring into cost efficient hiring regions. None of these are the sort of inspiring topics that excite folks, but they are all essential to the long term stability of your organization. Explaining engineering costs to boards/execs – Similarly, I finally have a clear perspective on how to represent R&D investment to boards in the same language that they speak in, which I wrote up here, and know how to do it quickly without relying on any manually curated internal datasets. Lots of smaller stuff, like the no wrong doors policy for routing colleagues to appropriate channels, how to request headcount in a way that is convincing to executives, Act Two rationales for how people’s motivations evolve over the course of long careers (and my own personal career mission to advance the industry, why friction isn’t velocity even though many folks act like it is. I’ve also learned quite a bit about venture capital, fund administration, cap tables, non-social network products, operating a multi-business line company, and various operating models. Figuring out how to sanitize those learnings to share the interesting tidbits without leaking internal details is a bit too painful, so I’m omitting them for now. Maybe some will be shareable in four or five years after my context goes sufficiently stale. As a closing thought, I just want to say how much I’ve appreciated the folks I’ve gotten to work with at Carta. From the executive team (Ali, April, Charly, Davis, Henry, Jeff, Nicole, Vrushali) to my directs (Adi, Ciera, Dan, Dave, Jasmine, Javier, Jayesh, Karen, Madhuri, Sam, Shawna) to the navigators (there’s a bunch of y’all). The people truly are always the best part, and that was certainly true at Carta.