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recent posts on blogs I follow


EDT with updating double counts

I recently got confused thinking about the following case: Calculator bet: I am offered the opportunity to bet on a mathematical statement X to which I initially assign 50% probability (perhaps X = 139926 is a quadratic residue modulo 314159). I have access to a calculator that is 99% reliable, i.e. it corrupts the answer … More EDT with updating double counts

via The sideways view October 12, 2021

Secure homes for digital people

Being a “digital person” could be scary—if I don’t have control over the hardware I’m running on, then someone else could get my code and run tons of copies in horrible conditions. (See also: qntm’s Lena.) It would be great to guarantee digital people some control over their situation: 1. to control their local environment … More Secure homes for digital people

via The sideways view October 10, 2021

Meditations on newborns

[Content: death.]I wrote most of this a couple of months ago when Nora was a newborn, but the first few months are not that conducive to finishing blog posts. New babies put you into a liminal period, both in your own experience and in how others treat you. People congratulate you on pregnancies and new […]

via The whole sky October 3, 2021

The value of in-house expertise

An alternate title for this post might be, "Twitter has a kernel team!?". At this point, I've heard that surprised exclamation enough that I've lost count of the number times that's been said to me (I'd guess that it's more than ten but less than a hundred). If we look at trendy companies that are within a couple factors of two in size of Twitter (in terms of either market cap or number of engineers), they mostly don't have similar expertise, often as a result of…

via Posts on Dan Luu September 29, 2021

Watch Team Backup

This is a useful concept that’s been written up in its original military context, but I wanted to write out how it’s also applicable in more mainstream settings. Amy Labenz introduced “watch team backup” to the Centre for Effective Altruism where we both work; Amy learned it from a friend who’d worked on a nuclear […]

via The whole sky September 27, 2021

What I've been doing instead of writing

I’ve been too busy with work to write much recently, but in lieu of that, here’s a batch of links to other stuff I’ve been doing elsewhere. The thing I’m most excited about: Wave raises $200m from Sequoia, Stripe, Founders Fund and Ribbit at a $1.7b valuation. It’ll fund faster expansion across Africa. I’m pumped for us to save tons of money + time for even more people!

via September 11, 2021

Some reasons to measure

A question I get asked with some frequency is: why bother measuring X, why not build something instead? More bluntly, in a recent conversation with a newsletter author, his comment on some future measurement projects I wanted to do (in the same vein as other projects like keyboard vs. mouse, keyboard, terminal and end-to-end latency measurements) was, "so you just want to get to the top of Hacker News?" The implication for the former is that measuring is less valuable than building and f…

via Posts on Dan Luu August 27, 2021

Thoughts you mightn't'a thunk about remote meetings

Welcome to this week's edition of "building a startup in 2020," in which all your meetings are suddenly remote, and you probably weren't prepared for it. I know I wasn't. We started a "fully remote" company back in 2019, but that was supposed to mean we still got together in person every month or two to do strategic planning, share meals, and resolve any accumulated conflicts. Well, not this year. Instead, we had to learn to have better remote meetings, all while build…

via apenwarr July 21, 2021

Songs about terrible relationships

[Spoilers for several old musicals.] TV Tropes lists dozens of examples of the “I want” song (where the hero of a musical sings about their dream of escaping their small surroundings). After watching a bunch of musicals on maternity leave, I’m wondering how many examples there are of the song genre “I’ll never leave my […]

via The whole sky July 17, 2021

Improving capital gains taxes

As I’ve mentioned, I think the tax code could be improved. In a departure from my usual style, this post fleshes out some fairness-based arguments for one of my favorite changes. (I think that this proposal, and many of the arguments in favor, is old. Wikipedia quotes Joseph Stieglitz making the basic point in Economics … More Improving capital gains taxes

via The sideways view July 9, 2021


I love Nora. She is a really fun sister. I give her a hug and a kiss each night. Nora is pretty much always nearby so I can go and cuddle her. Unless she's nursing. Or sleeping. Or having her diaper changed. Which is a lot of the time. But, overall, Nora is a really really fun sister. She's also very silly, and she makes silly faces.

via Lily Wise's Blog Posts July 6, 2021

Several grumpy opinions about remote work at Tailscale

As a "fully remote work" company, we had to make some choices about the technologies we use to work together and stay in touch. We decided early on - about the time we realized all three cofounders live in different cities - that we were going to go all-in on remote work, at least for engineering, which for now is almost all our work. As several people have pointed out before, fully remote is generally more stable than partly remote. In a partially remote team, the remote workers seem to …

via apenwarr June 21, 2021

It's ok to feed stray cats

Before we had kids, Jeff and I fostered a couple of cats. One had feline AIDS and was very skinny. Despite our frugal grocery budget of the time, I put olive oil on her food, determined to get her healthier. I knew that stray cats were not a top global priority, and that this wasn’t even the best way of helping stray cats, but it was what I wanted to do.. . . . .The bike path near where I live has a lot of broken glass on the ground nearby. My family likes to go barefoot in the summer, and a lo…

via Giving Gladly May 15, 2021

Books and websites on babies

Several people I know are expecting a first baby soon, and I wrote up notes for one of them. Might as well share here too: Medical:Scott Alexander’s Biodeterminist’s Guide to Parenting is an interesting read, and some parts are actionable.  If you live in an old building (pre-1978 in the US), here’s my writeup on lead paint. […]

via The whole sky April 14, 2021

Notes from “Don’t Shoot the Dog”

I just finished Karen Pryor’s “Don’t Shoot the Dog: the New Art of Teaching and Training.” Partly because a friend points out that it’s not on Audible and therefore she can’t possibly read it, here are the notes I took and some thoughts. It’s a quick, easy read. The author started off as a dolphin […]

via The whole sky April 2, 2021

Media I Liked: Q1 2021

Music Dagny, Love You Like That (2017) Willow, Wait a Minute!, ARDIPITHECUS (2015) Blue Kid, The Dismemberment Song, Upright, Love (2012) Gregory and the Hawk, The Bolder Thing To Do (Demo Version), Self-Titled Demo (2007) Frances Forever, treehouse, pockets (2018) Cavetown, Boys Will Be Bugs, Animal Kingdom: Comet (2018) UPSAHL, Drugs (2019) Destructo Disk, I Wish I Was A Riot Grrrl, Punk Rocks For Kids Who Can't Skate (2018) Sidney Gish, Impostor Syndrome, No Dogs Allowed (2017) The Derevolutions, …

via BLOG - Cullen O'Keefe March 28, 2021

Demand offsetting

For the last few years I’ve been avoiding factory farmed eggs because I think they involve a lot of unnecessary suffering. I’m hesitant to be part of that even if it’s not a big deal on utilitarian grounds. This is a pain since factory-farmed eggs are used all over the place (e.g. in ice cream, … More Demand offsetting

via The sideways view March 21, 2021

The Troubling Ethics of Writing (A Speech from Ancient Sumer)

(Translated from a transcript of an ancient Sumerian speech by Uruk's most well-respected Scriptological Ethicist) Writing is a profoundly dangerous technology: Access to writing was initially, and still remains, uneven. What's worse, the rich are more likely to be literate, so it not only creates inequalities but exacerbates existing ones. Written language embodies the biases and prejudices of the people responsible for writing. Writing makes those prejudices more permanent and influentia…

via BLOG - Cullen O'Keefe February 15, 2021

Blameworthiness for Avoidable Psychological Harms

When a harm is created as a result of both external actions and a psychological reaction, how should we apportion blame?

via BLOG - Cullen O'Keefe February 9, 2021


Today I made valentines. I made fruit valentines. There were orange fruit valentines, and grape fruit valentines, watermelon fruit valentines, and pineapple too. I made them for my classmates and teacher. They had a little jokes or puns on the back. The jokes or puns were on a sticker that we could stick on the back. I stuck on googly eyes, and I drew a mouth. I added hearts and a sticker. That's how I made the valentines. Here is a picture so you can see some of my valentines:

via Lily Wise's Blog Posts January 23, 2021

My 2020 Giving

2020 Giving in ContextIn 2020, I donated $ 24,918.01. By organization, these were:Legal Priorities Project: $ 10,005.50Long-Term Future EA Fund: $ 8,036.00Joe Biden for President: $ 2,800GiveWell (regrant): $ 1,551Center for Election Science: $ 1,000Charter Cities Institute: $ 1,000EA Cameroon: $ 250Against Malaria Foundation: $ 120GiveDirectly: $ 83.51Malaria Consortium: $ 30Nuclear Threat Initiative: $ 22Wild Animal Initiative: $ 10MIRI: $ 10This does not include donations made on my behalf a…

via BLOG - Cullen O'Keefe January 5, 2021

Systems design explains the world: volume 1

"Systems design" is a branch of study that tries to find universal architectural patterns that are valid across disciplines. You might think that's not a possibility. Back in university, students used to tease the Systems Design Engineers, calling it "boxes and arrows" engineering. Not real engineering, you see, since it didn't touch anything tangible, like buildings, motors, hydrochloric acid, or, uh, electrons. I don't think the Systems Design people took this critici…

via apenwarr December 29, 2020

Against essential and accidental complexity

In the classic 1986 essay, No Silver Bullet, Fred Brooks argued that there is, in some sense, not that much that can be done to improve programmer productivity. His line of reasoning is that programming tasks contain a core of essential/conceptual1 complexity that's fundamentally not amenable to attack by any potential advances in technology (such as languages or tooling). He then uses an Ahmdahl's law argument, saying that because 1/X of complexity is essential, it's impossible to …

via Posts on Dan Luu December 29, 2020

Milk Experiments

I mixed milk with some colored pigment. First, the color spread a little tiny bit. And then when we added we added some dish soap the colors spread and a big colorful wave.

via Lily Wise's Blog Posts December 27, 2020

Media I Liked: Q4 2020

Inspired by Luke Muehlhauser, I'm going to try to start using my blog to highlight some media I've enjoyed over the past ~quarter. Since this is my first post, this contains some stuff especially I liked in Q3 as well. Music Will Wood, The Normal Album (2020) ミラクルミュージカル, Hawaii: Part II (2012) Lots of stuff by Billy Cobb, especially: Zerwee (2020) Zerwee, Pt. 2 (2020) Rocky Horror, on Strokes of Incarceration (2018) Lots of stuff by Beach Bunny, especially: Prom Queen, on Prom Queen (2…

via BLOG - Cullen O'Keefe December 26, 2020

My favorite essays of life advice

Life is short • There is no speed limit • How to Be Successful • You and your research • Becoming a Magician • 95th percentile isn’t that good

via December 23, 2020

To listen well, get curious

When I’ve listened the most effectively to people, it’s because I was intensely curious—I was trying to build a detailed, precise understanding of what was going on in their head.

via December 12, 2020

In defense of blub studies

Why it’s worth it to deeply understand the fiddly, boring-seeming details of the computer systems you use every day.

via December 5, 2020

Can I work for a bad company and still be a good person?


via apenwarr November 23, 2020

It’s not economically inefficient for a UBI to reduce recipient’s employment

A UBI (e.g. paying every adult American $8k/year) would reduce recipient’s need for money and so may reduce their incentive to work. This is frequently offered as an argument against a UBI (or as an argument for alternative policies like the EITC that directly incentivize work). This argument is sometimes presented as economically hard-headed realism. … More It’s not economically inefficient for a UBI to reduce recipient’s employment

via The sideways view November 22, 2020

How to make video calls almost as good as face-to-face

I spent way too long figuring out the how to make video calls feel natural. Here’s the best advice I came up with.

via September 27, 2020

Learning Game

I came up with this game. In the game one person thinks of something and then gives the other person a clue. And the other person writes a guess down on a blackboard or a piece of paper. Or really anything you have that's laying around that's available for writing on. The other person says whether it's right or wrong. And then when they get it right the other person takes a turn. When they get it wrong the other person gives them another clue and they guess again. It has to be clos…

via Lily Wise's Blog Posts September 17, 2020


This is jewelry I made, but I didn't really make all of them. My au pair Erika made a few of them but I made most of them. I made at least six of them. Erika made two. Free delivery within a half hour bike ride of West Somerville. Otherwise I will send it to you in the mail. You pay for shipping. Email my dad, Jeff ( if you want to buy something. Butterfly Bracelet It costs $8. I was thinking about butterflies when I made this bracelet. Pom-pom Bracelet I was thinking about pom-p…

via Lily Wise's Blog Posts August 27, 2020

IPv4, IPv6, and a sudden change in attitude

A few years ago I wrote The World in Which IPv6 was a Good Design. I'm still proud of that article, but I thought I should update it a bit. No, I'm not switching sides. IPv6 is just as far away from universal adoption, or being a "good design" for our world, as it was three years ago. But since then I co-founded a company that turned out to be accidentally based on the principles I outlined in that article. Or rather, from turning those principles upside-down. In that article, I exp…

via apenwarr July 22, 2020

How do cars fare in crash tests they're not specifically optimized for?

Any time you have a benchmark that gets taken seriously, some people will start gaming the benchmark. Some famous examples in computing are the CPU benchmark specfp and video game benchmarks. With specfp, Sun managed to increase its score on (a sub-benchmark of specfp) by 12x with a compiler tweak that essentially re-wrote the benchmark kernel, which increased the Sun UltraSPARC’s overall specfp score by 20%. At times, GPU vendors have added specialized benchmark-detecting code to their…

via Posts on Dan Luu June 30, 2020

A simple way to get more value from tracing

A lot of people seem to think that distributed tracing isn't useful, or at least not without extreme effort that isn't worth it for companies smaller than FB. For example, here are a couple of public conversations that sound like a number of private conversations I've had. Sure, there's value somewhere, but it costs too much to unlock. I think this overestimates how much work it is to get a lot of value from tracing. At Twitter, Rebecca Isaacs was able to lay out a vision for how…

via Posts on Dan Luu May 31, 2020

You have more than one goal, and that's fine

When people come to an effective altruism event for the first time, the conversation often turns to projects they’re pursuing or charities they donate to. They often have a sense of nervousness around this, a feeling that the harsh light of cost-effectiveness is about to be turned on everything they do. To be fair, this is a reasonable thing to be apprehensive about, because many youngish people in EA do in fact have this idea that everything in life should be governed by cost-effectiveness. I&…

via Giving Gladly February 19, 2019

No one is a statistic

I’m late to the party, but I've been thinking about the documentary “The Life Equation” about how people use data to decide make life-and-death decisions. The central example is a woman named Crecencia, a mother of seven who lives in rural Guatemala and has cervical cancer. The doctor treating her knows that screening other women for cancer is more cost-effective than treating this woman, and that the community doesn’t have enough money to fully fund both. The filmmaker writes: “Crecencia’s…

via Giving Gladly October 10, 2018

Two standard donations and one new one

Here are three places Jeff and I are donating this year. The first two are similar to what we’ve been doing for years, and the third represents a change.Direct workJeff and I want to support work that directly makes the world a better place. (Some arguments against falling into a “meta trap” here.) As usual for us, this year we’ve given just over half our donations to direct work. We made these donations to the Against Malaria Foundation, one of GiveWell’s top picks, except for small amounts th…

via Giving Gladly December 30, 2016

Practical steps for self-care

Last week the Boston Effective Altruism group had a discussion on self-care for altruists. I've written about the topic before, but I wanted to share some of the more practical advice people had. Think beyond day-to-day choicesSelf-care isn’t just short-term decisions like whether to make time for yoga tonight. It’s larger life decisions too, like what job to take, where to live, how to budget money, and how to make time for partners, friends, and family.For me, having children was self-car…

via Giving Gladly June 15, 2016

via openring