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I've been biking in Brooklyn for a few years now! It's hard for me to believe it, but I'm now one of the people other bicyclists ask questions to now. I decided to make a zine that answers the most common of those questions: Bike Brooklyn! is a zine that touches on everything I wish I knew when I started biking in Brooklyn. A lot of this information can be found in other resources, but I wanted to collect it in one place. I hope to update this zine when we get significantly more safe bike infrastructure in Brooklyn and laws change to make streets safer for bicyclists (and everyone) over time, but it's still important to note that each release will reflect a specific snapshot in time of bicycling in Brooklyn. All text and illustrations in the zine are my own. Thank you to Matt Denys, Geoffrey Thomas, Alex Morano, Saskia Haegens, Vishnu Reddy, Ben Turndorf, Thomas Nayem-Huzij, and Ryan Christman for suggestions for content and help with proofreading. This zine is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, so you can copy and distribute this zine for noncommercial purposes in unadapted form as long as you give credit to me. Check out the Bike Brooklyn! zine on the web or download pdfs to read digitally or print here!
I found inspiration for this pitcher's glaze design in the night sky. Whenever I feel lost, I know I can always look up and be under the same night sky, no matter where I am. Whenever I feel alone, I know I can always look up and feel connected to humanity, everyone else looking up at the same sky. Whenever I feel all is lost, the vast darkness in the night sky reminds me there are so many possibilities out there that I haven't even thought of yet. My studio practice is on a partial pause for an unknown amount of time right now; every piece I make is stuck in the greenware stage as I continue to save up to buy kilns and build out the glaze and kiln area. In some moments, this pause feels like a rare opportunity to take time to make more experimental and labor intensive pieces, but in other moments, I am overwhelmed by the feeling that pieces without a completion timeline on the horizon are just not worth doing. It's easy to bask in fleeting bursts of inspiration; it's harder to push through the periods where nothing feels worth doing. It's especially when the waves of anxiety about the unknown future of my studio practice and the waves of anxiety about the direction of the US government and the future of my country come at me at the same time. I try to ground myself, to keep myself from spiraling. I name things I can see, smell, hear. At night, I look to the dark sky. When I can, I reread Rebecca Solnit's Hope in the Dark: Hope locates itself in the premises that we don't know what will happen and that in the spaciousness of uncertainty is room to act. When you recognize uncertainty, you recognize that you may be able to influence the outcomes–you alone or you in concert with a few dozen or several million others. Hope is an embrace of the unknown and the unknowable, an alternative to the certainty of both optimists and pessimists. Optimists think it will all be fine without our involvement; pessimists take the opposite position; both excuse themselves from acting. It's the belief that what we do matters even though how and when it may matter, who and what it may impact, are not things we can know beforehand. We may not, in fact, know them afterward either, but they matter all the same, and history is full of people whose influence was most powerful after they were gone. May we all find hope in the dark and choose to act.
When I was glazing this v60-style cone, I was thinking of rising sea levels, eroding beaches, and melting ice caps. Trying to tackle large challenges like climate change is overwhelming in the best of times, and these are not the best of times. There are many things we can personally do to reduce our carbon footprints and fight climate change, but If we want to have any chance to succeed, we need to join together and organize. If you're new to organizing, connect with local groups already doing the work you're interested in, and don't forget to look for groups pushing for change outside of just the national stage. Creating more dense walkable, transit-oriented communities is one of our strongest tools for a sustainable, climate friendly future. Generally, the bulk this work in the US happens at the state and local levels. In addition to the climate benefits, it's essential work to keep communities together and fight displacement. I personally spend a lot of my spare time organizing locally around this issue to help ensure NYC and New York State stay places everyone can thrive. I focus especially on pro-housing policies and improving transportation options and reliability so climate-friendly, less car-dependent lifestyles - and New York's relative safety - can be for everyone.
Clay shrinks as it dries and even more as it's fired, so it's useful to have a way to estimate the final size of in-progress work - especially if you're making multiples or trying to fit pieces together. One way to do this is with shrinkage rulers. I figured I'd design my own shrinkage rulers and provide a way for folks to make them themselves since ceramic tool costs can add up. To make your shrinkage rulers: Download either the colorful printable shrinkage rulers or black and white printable shrinkage rulers. Print at 100% size. (These files are both 400 dpi.) Verify that the 0% shrinkage standard ruler at the top matches the size of an existing regular ruler you have. This quick calibration step will make sure nothing out of scale during printing! Cut out your rulers. Optionally, laminate or cover in packing tape to help them last longer. To use your shrinkage rulers: If you're using commercial clay, look up how much your clay is estimated to shrink. If you're using a blend of clays or custom clays, you'll have to calculate how much your clay shrinks. An easy way to do this is measure the length of a wet piece right after you form them and again after it's been through its glaze firing. You can then calculate the estimated shrinkage rate: Pick the shrinkage ruler that corresponds to your clay's shrinkage rate. If you're between shrinkage rates, you can estimate with a nearby size. Remember that shrinkage rates are estimates, and a piece's actual shrinkage depends on many variables, including how wet your clay is and how close it is to it's original composition (this can change with repeated recycling). Measure your wet piece with the shrinkage ruler! The length shown is the expected length your piece's dimension will be when fired. The fine print: Reminder that shrinkage rulers only give estimated lengths! You're welcome to print these shrinkage rulers for yourself or your business. You may use the printed shrinkage rulers privately, even in commercial applications (I hope they help your ceramic art and business!), provided you do not redistribute or resell the shrinkage rulers themselves in any form, digital or physical. Footnotes If you're working on a jar or something else that needs to fit together tightly, it's better not to rely on shrinkage rulers to get a perfect fit. In my experiences, you ideally want to make the vessel and the lid as close in time as possible and have them dry together and fire together through as many phases as possible.↩
I'm continuing my clay body reviews series with two very heavily grogged "sculpture" clays I've used. Note that I currently practice in a community studio that glaze fires to cone 6 in oxidation, so my observations reflect that. Standard 420 Sculpture: Cone 6: average shrinkage 8.0%, absorption 1.5% Light straw when fired to cone 6: more yellow/beige than most white stonewares so the color is something to consider in your final vision (or engobe in something else) So much grog that it’s best described as working with wet sand, non-derogatory I've made complicated open coil-based structures with this clay that have been formed across many studio sessions over a couple days, and they've survived without cracking! Wet clay attaches readily to leather hard and even slightly dry clay. Wrapping my works in dry cleaning bags until done and dry before bisque was enough - I was worried I'd have to make a damp box, but not with this clay! The grog is white and grey, and it comes in a variety of sizes, including some that is visually rather large. The grog really shows if you sand to smooth the surface. I typically dislike how this looks - the result ends up looking more like concrete than clay. If you use this for functional ware or anything you move around a lot, you'll certainly want to sand the bottom since the groggy surface is extra rough to protect tables and counters. Burnishing alone doesn't usually make this clay smooth. Can be thrown when very soft, but your hands will feel scratched if you're not used to it! Angled slab joins join readily, and support coils press in quickly and easily. Some members of my studio prefer to make plates with this clay because the high level of grog significantly reduces warping. I personally prefer to make plates with clays with far less grog that I dry very slowly. High palpable grog content means a weaker object, and I prefer more strength in objects that are handled frequently. Can be marbled with 798, but needs to dry slowly. Standard 420's straw color shows in the unglazed section of this planter's drip tray, and there's also some flashing from the glaze near the edges. I sanded the base of this piece so the slightly rough surface of Standard 420 wouldn't scratch tables, and you can see the contrast between the sanded bottom (outside) layer where the varied grogs are revealed and the rougher surfaces of the other layers where they are still covered by clay particles. This handbuilt planter was made of Standard 798 over multiple studio sessions. The sculptural coil structures attached readily with my regular slip and score process, and it dried evenly enough to not crack with my regular process of drying under a single plastic dry-cleaning bag. This coiled wall art piece was made out of equal parts Standard 112 and Standard 420 wedged fully together. There's still ample grog in this hybrid clay body to work the same as the Standard 798 planter's coiled structure. Standard 798 Black Sculpture: Cone 6: average shrinkage 10%, absorption 1.0% Dark brown when wet, fires to a gorgeous black at cone 6 when unglazed. Clear glazes will make this clay look brown, so you need to use a black like Coyote Black or Amaco Obsidian to preserve the black color if you want to glaze it. So much grog that it’s best described as working with wet sand, non-derogatory. The grog is white, and provides a lovely contrast when on the surface or sanded to be revealed. Like 420, you'll probably want to sand the bottom of anything you'll pick up and put down more than once. Very similar working qualities to 420 - a true joy for handbuilding! Can be marbled with 420, but needs to dry slowly.
More in programming
The first in a series of posts about doing things the right way
A deep dive into the Action Cache, the CAS, and the security issues that arise from using Bazel with a remote cache but without remote execution
(I present to you my stream of consciousness on the topic of casing as it applies to the web platform.) I’m reading about the new command and commandfor attributes — which I’m super excited about, declarative behavior invocation in HTML? YES PLEASE!! — and one thing that strikes me is the casing in these APIs. For example, the command attribute has a variety of values in HTML which correspond to APIs in JavaScript. The show-popover attribute value maps to .showPopover() in JavaScript. hide-popover maps to .hidePopover(), etc. So what we have is: lowercase in attribute names e.g. commandfor="..." kebab-case in attribute values e.g. show-popover camelCase for JS counterparts e.g. showPopover() After thinking about this a little more, I remember that HTML attributes names are case insensitive, so the browser will normalize them to lowercase during parsing. Given that, I suppose you could write commandFor="..." but it’s effectively the same. Ok, lowercase attribute names in HTML makes sense. The related popover attributes follow the same convention: popovertarget popovertargetaction And there are many other attribute names in HTML that are lowercase, e.g.: maxlength novalidate contenteditable autocomplete formenctype So that all makes sense. But wait, there are some attribute names with hyphens in them, like aria-label="..." and data-value="...". So why isn’t it command-for="..."? Well, upon further reflection, I suppose those attributes were named that way for extensibility’s sake: they are essentially wildcard attributes that represent a family of attributes that are all under the same namespace: aria-* and data-*. But wait, isn’t that an argument for doing popover-target and popover-target-action? Or command and command-for? But wait (I keep saying that) there are kebab-case attribute names in HTML — like http-equiv on the <meta> tag, or accept-charset on the form tag — but those seem more like legacy exceptions. It seems like the only answer here is: there is no rule. Naming is driven by convention and decisions are made on a case-by-case basis. But if I had to summarize, it would probably be that the default casing for new APIs tends to follow the rules I outlined at the start (and what’s reflected in the new command APIs): lowercase for HTML attributes names kebab-case for HTML attribute values camelCase for JS counterparts Let’s not even get into SVG attribute names We need one of those “bless this mess” signs that we can hang over the World Wide Web. Email · Mastodon · Bluesky
Greetings everyone! You might have noticed that it's September and I don't have the next version of Logic for Programmers ready. As penance, here's ten free copies of the book. So a few months ago I wrote a newsletter about how we use nondeterminism in formal methods. The overarching idea: Nondeterminism is when multiple paths are possible from a starting state. A system preserves a property if it holds on all possible paths. If even one path violates the property, then we have a bug. An intuitive model of this is that for this is that when faced with a nondeterministic choice, the system always makes the worst possible choice. This is sometimes called demonic nondeterminism and is favored in formal methods because we are paranoid to a fault. The opposite would be angelic nondeterminism, where the system always makes the best possible choice. A property then holds if any possible path satisfies that property.1 This is not as common in FM, but it still has its uses! "Players can access the secret level" or "We can always shut down the computer" are reachability properties, that something is possible even if not actually done. In broader computer science research, I'd say that angelic nondeterminism is more popular, due to its widespread use in complexity analysis and programming languages. Complexity Analysis P is the set of all "decision problems" (basically, boolean functions) can be solved in polynomial time: there's an algorithm that's worst-case in O(n), O(n²), O(n³), etc.2 NP is the set of all problems that can be solved in polynomial time by an algorithm with angelic nondeterminism.3 For example, the question "does list l contain x" can be solved in O(1) time by a nondeterministic algorithm: fun is_member(l: List[T], x: T): bool { if l == [] {return false}; guess i in 0..<(len(l)-1); return l[i] == x; } Say call is_member([a, b, c, d], c). The best possible choice would be to guess i = 2, which would correctly return true. Now call is_member([a, b], d). No matter what we guess, the algorithm correctly returns false. and just return false. Ergo, O(1). NP stands for "Nondeterministic Polynomial". (And I just now realized something pretty cool: you can say that P is the set of all problems solvable in polynomial time under demonic nondeterminism, which is a nice parallel between the two classes.) Computer scientists have proven that angelic nondeterminism doesn't give us any more "power": there are no problems solvable with AN that aren't also solvable deterministically. The big question is whether AN is more efficient: it is widely believed, but not proven, that there are problems in NP but not in P. Most famously, "Is there any variable assignment that makes this boolean formula true?" A polynomial AN algorithm is again easy: fun SAT(f(x1, x2, …: bool): bool): bool { N = num_params(f) for i in 1..=num_params(f) { guess x_i in {true, false} } return f(x_1, x_2, …) } The best deterministic algorithms we have to solve the same problem are worst-case exponential with the number of boolean parameters. This a real frustrating problem because real computers don't have angelic nondeterminism, so problems like SAT remain hard. We can solve most "well-behaved" instances of the problem in reasonable time, but the worst-case instances get intractable real fast. Means of Abstraction We can directly turn an AN algorithm into a (possibly much slower) deterministic algorithm, such as by backtracking. This makes AN a pretty good abstraction over what an algorithm is doing. Does the regex (a+b)\1+ match "abaabaabaab"? Yes, if the regex engine nondeterministically guesses that it needs to start at the third letter and make the group aab. How does my PL's regex implementation find that match? I dunno, backtracking or NFA construction or something, I don't need to know the deterministic specifics in order to use the nondeterministic abstraction. Neel Krishnaswami has a great definition of 'declarative language': "any language with a semantics has some nontrivial existential quantifiers in it". I'm not sure if this is identical to saying "a language with an angelic nondeterministic abstraction", but they must be pretty close, and all of his examples match: SQL's selects and joins Parsing DSLs Logic programming's unification Constraint solving On top of that I'd add CSS selectors and planner's actions; all nondeterministic abstractions over a deterministic implementation. He also says that the things programmers hate most in declarative languages are features that "that expose the operational model": constraint solver search strategies, Prolog cuts, regex backreferences, etc. Which again matches my experiences with angelic nondeterminism: I dread features that force me to understand the deterministic implementation. But they're necessary, since P probably != NP and so we need to worry about operational optimizations. Eldritch Nondeterminism If you need to know the ratio of good/bad paths, the number of good paths, or probability, or anything more than "there is a good path" or "there is a bad path", you are beyond the reach of heaven or hell. Angelic and demonic nondeterminism are duals: angelic returns "yes" if some choice: correct and demonic returns "no" if !all choice: correct, which is the same as some choice: !correct. ↩ Pet peeve about Big-O notation: O(n²) is the set of all algorithms that, for sufficiently large problem sizes, grow no faster that quadratically. "Bubblesort has O(n²) complexity" should be written Bubblesort in O(n²), not Bubblesort = O(n²). ↩ To be precise, solvable in polynomial time by a Nondeterministic Turing Machine, a very particular model of computation. We can broadly talk about P and NP without framing everything in terms of Turing machines, but some details of complexity classes (like the existence "weak NP-hardness") kinda need Turing machines to make sense. ↩
The 2025 edition of the TokyoDev Developer Survey is now live! If you’re a software developer living in Japan, please take a few minutes to participate. All questions are optional, and it should take less than 10 minutes to complete. The survey will remain open until September 30th. Last year, we received over 800 responses. Highlights included: Median compensation remained stable. The pay gap between international and Japanese companies narrowed to 47%. Fewer respondents had the option to work fully remotely. For 2025, we’ve added several new questions, including a dedicated section on one of the most talked-about topics in development today: AI. The survey is completely anonymous, and only aggregated results will be shared—never personally identifiable information. The more responses we get, the deeper and more meaningful our insights will be. Please help by taking the survey and sharing it with your peers!
