Every time I get a new phone it feels a bit like magic : I no longer need to think at all about battery life. This lasts for a few years, and then at some point my phone doesn't always make it through the day. Some amount of this is normal, but some of it is just bad battery management: new phones should come set not…
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On July 1st I discovered a puddle of liquid mercury in our house. It was the evening before the holiday weekend and I was preparing to do some more demolition for the bathroom I've been working on. I was putting down plastic to make cleanup easier, and when I got to the corner there was a dusty little puddle. That…
"I work on ads at Google" "Can I ask why? I honestly can't understand how anyone could." Someone recently asked me why I work on ads, and I wanted to write up something more thorough than my comment. (Despite being a work topic this is a personal post and I'm speaking only for myself.) One answer is that I'm earning…
(As with anything else I write about parenting, this is mostly just my observations with my own two kids and may not generalize as well as I think it does.) A few weeks ago I wrote about why I think it's valuable for parents to be predictable. I was mostly describing an end state, though, and reasons why it's a good…
Sometimes people will talk about Chesterton's Fence, the idea that if you want to change something—removing an apparently useless fence—you should first determine why it was set up that way: The gate or fence did not grow there. It was not set up by somnambulists who built it in their sleep. It is highly…
A week ago the Copy Fail vulnerability came out, and Hyunwoo Kim immediately realized that the fixes were insufficient, sharing a patch the same day. In doing this he followed standard procedure for Linux, especially within networking: share the security impact with a closed list of Linux security engineers, while…
It's common for me to get excited about a personal project, put a bunch of time into it, and then lose interest. As much as possible, I want these projects to continue working; upkeep isn't fun. What does designing for minimum maintenance look like? The biggest piece is minimizing your dependencies, and limiting them…
Browsers historically have had a single HTTP Cache. This meant that if www.a.example and www.b.example both used cdn.example/jquery-1.2.1.js then JQuery would only be downloaded once. Since it's the same resource regardless of which site initiates the download, a single shared cache is more efficient. [1]…
Summary: we don't understand why programmers are paid so well. If you're a programmer, there's enough of a chance that this is temporary that it's worth explicitly planning for a future in which you're laid off and unable to find similarly high-paying work. Programmers are paid surprisingly well given how much work it…
Let's say you use a Google account as the root of your online identity: Gmail, Fi, "Sign in with Google", Google's password manager, etc. How much should you be worried that you'll suddenly find yourself unable to get into everything? Should you do something else instead? To get a sense of how common lockouts are and…
You famously only need four chords to play everything, or maybe it's only three. But how true is this really? I decided to go look and see what was common. I looked at a large number of transcribed songs, writing down which chords were used. This isn't perfect: some chords are more optional than others, but it's about…
I remember when mosh first came out and thinking "that sounds like a great idea, maybe I'll set it up sometime" and then never getting around to it. Several times over the years I've thought similarly, but it never seemed worth it. A week ago a coworker asked if there were good tools for handling remote terminal use…
We used to make land. We built long wharves for docking ships, and then over time filled in the areas between them. Later we built up mudflats wholesale to make even larger areas. Here's a map of Boston showing how much of the land wasn't previously dry: (Map reproduction courtesy of the Norman B. Leventhal Map &…
A few years ago I wrote about how I'd been playing a simplified version of Carcassonne with Lily. We stopped for a while, but recently we've played simplified versions of Ticket to Ride, Race for the Galaxy, Guillotine, and Settlers of Catan. My general approach here is to find a core piece of the game that will be…
Imagine a high-capacity air filter that is extremely quiet and doesn't get in the way. I think I see how to build one; here's a prototype: By putting a fan on the ceiling you can have very long blades. This is important for keeping noise down: the longer your blades are the more air you move at a given rotational…
When coding a webpage, sometimes you know something is very likely to be needed, even if it's not needed yet. You can give the browser a hint: <link rel=prefetch href=url> The browser will take a note, and then when it doesn't have anything more important to do it might request url. Later on, if it does turn out…
Sometimes you have a lot of data, and one approach to support quick searches is pre-processing it to build an index so a search can involve only looking at a small fraction of the total data. The threshold at which it's worth switching to indexing, though, might be higher than you'd guess. Here are some cases I've…
I generally find the numbers printed on pasta boxes for cooking time far too high: I'll set the timer for a minute below their low-end "al dente" time, and when I taste one it's already getting too mushy. I decided to run a small experiment to get a better sense of how cooked I like pasta. I decided to use Market…
The FAA has one of my favorite examples of thoughtful rulemaking. They haven't banned flying with a baby on your lap, because the extra cost would mean many parents would drive instead. Since driving is far less safe than flying, a ban would lead to more deaths. I'd love to see more of this "all things considered"…
Your terminal can display color, but most diff tools don't make good use of it. By highlighting changes, icdiff can show you the differences between similar files without getting in the way. This is especially helpful for identifying and understanding small changes within existing lines.
White noise machines are widely used for sound masking, increasing privacy in offices and helping people sleep. The classic approach is a fan in a box, though in the past ten years people have mostly switched over to electronic ones. But a fan is really a great approach; you just need to put it to better use: have the…
Content warning: risk to children Julia and I know drowning is the biggest risk to US kids 1-4, and we try to take this seriously. But yesterday our 4yo came very close to drowning in a fountain. (She's fine now.) This week we were on vacation with my extended family: nine kids, eight parents, and ten…
EDIT 2026-07-08: Gizmohub, despite the announcements, did not stop working on the 7th. Instead, a Verizon tech called me, and told me that they were not going to take Gizmohub down until they'd resolved these issues. They also walked me through getting set up, including getting me the 2FA code that was not coming…
In dry climates it's common for people to use evaporative ("swamp") coolers; same idea as sweat evaporating off your skin cooling you off. The downside is that they increase humidity in the air, and if it's already pretty humid then that can make things uncomfortable. This means evaporative coolers are rarely used…
When I argue that we should bring rents down by building more housing, one kind of response I've gotten is: Why are you trying to move more people into cities? There's lots of housing available in the US, it's just not in the currently trendy cities. Instead of moving people we should be moving jobs. Why couldn't…
Jeffrey Yasskin recently pointed out an interesting security bug: The idea is, if you had registered googlelogoligature.net then Chrome on Android (and possibly other Google products) would have displayed it as Google.net, potentially tricking users into thinking they were really interacting with Google. To see how…
We just had a huge shift from people eating out to eating in, and now a lot more people are baking, so we and a lot of people I know have had trouble finding grocery stores with flour in stock. The residential supply chain is struggling to keep up with demand. On the other hand, the commercial supply chain is…
David asked a great question on my solar battery system post: why buy a small battery just for emergencies when electric cars have a large battery you can also use for other things? [1] This would be great, and seems like the obvious way for it to work: when the grid goes down the panels can charge the car when it's…
Unicode is just too complex to ever be secure.  — Bruce Schneier, 2000 Over the last 25 years Unicode has succeeded. It hasn't displaced all other character encodings, but it's clearly on its way there. It's supported widely enough that it's a compatible choice, new projects use it, and it's becoming the…
Before our kids learned to talk, I would play tickles with them. I would make tickling gestures as I moved towards them, they would start giggling a little, then I would tickle them and they would laugh. We'd continue until they seemed to be done with the game, and then we'd move on to something else. As they got…
If you want to make a long-term bet one of your options is to register your bet with the Long Now Foundation as a Long Bet. They have some rules, which are roughly: Both parties put up the same amount, at least $200/each. Long Bets effectively runs a donor-advised fund (DAF). When the bet concludes the winner chooses…