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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
A little while back I heard about the White House launching their version of a Drudge Report style website called White House Wire. According to Axios, a White House official said the site’s purpose was to serve as “a place for supporters of the president’s agenda to get the real news all in one place”. So a link blog, if you will. As a self-professed connoisseur of websites and link blogs, this got me thinking: “I wonder what kind of links they’re considering as ‘real news’ and what they’re linking to?” So I decided to do quick analysis using Quadratic, a programmable spreadsheet where you can write code and return values to a 2d interface of rows and columns. I wrote some JavaScript to: Fetch the HTML page at whitehouse.gov/wire Parse it with cheerio Select all the external links on the page Return a list of links and their headline text In a few minutes I had a quick analysis of what kind of links were on the page: This immediately sparked my curiosity to know more about the meta information around the links, like: If you grouped all the links together, which sites get linked to the most? What kind of interesting data could you pull from the headlines they’re writing, like the most frequently used words? What if you did this analysis, but with snapshots of the website over time (rather than just the current moment)? So I got to building. Quadratic today doesn’t yet have the ability for your spreadsheet to run in the background on a schedule and append data. So I had to look elsewhere for a little extra functionality. My mind went to val.town which lets you write little scripts that can 1) run on a schedule (cron), 2) store information (blobs), and 3) retrieve stored information via their API. After a quick read of their docs, I figured out how to write a little script that’ll run once a day, scrape the site, and save the resulting HTML page in their key/value storage. From there, I was back to Quadratic writing code to talk to val.town’s API and retrieve my HTML, parse it, and turn it into good, structured data. There were some things I had to do, like: Fine-tune how I select all the editorial links on the page from the source HTML (I didn’t want, for example, to include external links to the White House’s social pages which appear on every page). This required a little finessing, but I eventually got a collection of links that corresponded to what I was seeing on the page. Parse the links and pull out the top-level domains so I could group links by domain occurrence. Create charts and graphs to visualize the structured data I had created. Selfish plug: Quadratic made this all super easy, as I could program in JavaScript and use third-party tools like tldts to do the analysis, all while visualizing my output on a 2d grid in real-time which made for a super fast feedback loop! Once I got all that done, I just had to sit back and wait for the HTML snapshots to begin accumulating! It’s been about a month and a half since I started this and I have about fifty days worth of data. The results? Here’s the top 10 domains that the White House Wire links to (by occurrence), from May 8 to June 24, 2025: youtube.com (133) foxnews.com (72) thepostmillennial.com (67) foxbusiness.com (66) breitbart.com (64) x.com (63) reuters.com (51) truthsocial.com (48) nypost.com (47) dailywire.com (36) From the links, here’s a word cloud of the most commonly recurring words in the link headlines: “trump” (343) “president” (145) “us” (134) “big” (131) “bill” (127) “beautiful” (113) “trumps” (92) “one” (72) “million” (57) “house” (56) The data and these graphs are all in my spreadsheet, so I can open it up whenever I want to see the latest data and re-run my script to pull the latest from val.town. In response to the new data that comes in, the spreadsheet automatically parses it, turn it into links, and updates the graphs. Cool! If you want to check out the spreadsheet — sorry! My API key for val.town is in it (“secrets management” is on the roadmap). But I created a duplicate where I inlined the data from the API (rather than the code which dynamically pulls it) which you can check out here at your convenience. Email · Mastodon · Bluesky
Kubernetes is not exactly the most fun piece of technology around. Learning it isn’t easy, and learning the surrounding ecosystem is even harder. Even those who have managed to tame it are still afraid of getting paged by an ETCD cluster corruption, a Kubelet certificate expiration, or the DNS breaking down (and somehow, it’s always the DNS). Samuel Sianipar If you’re like me, the thought of making your own orchestrator has crossed your mind a few times. The result would, of course, be a magical piece of technology that is both simple to learn and wouldn’t break down every weekend. Sadly, the task seems daunting. Kubernetes is a multi-million lines of code project which has been worked on for more than a decade. The good thing is someone wrote a book that can serve as a good starting point to explore the idea of building our own container orchestrator. This book is named “Build an Orchestrator in Go”, written by Tim Boring, published by Manning. The tasks The basic unit of our container orchestrator is called a “task”. A task represents a single container. It contains configuration data, like the container’s name, image and exposed ports. Most importantly, it indicates the container state, and so acts as a state machine. The state of a task can be Pending, Scheduled, Running, Completed or Failed. Each task will need to interact with a container runtime, through a client. In the book, we use Docker (aka Moby). The client will get its configuration from the task and then proceed to pull the image, create the container and start it. When it is time to finish the task, it will stop the container and remove it. The workers Above the task, we have workers. Each machine in the cluster runs a worker. Workers expose an API through which they receive commands. Those commands are added to a queue to be processed asynchronously. When the queue gets processed, the worker will start or stop tasks using the container client. In addition to exposing the ability to start and stop tasks, the worker must be able to list all the tasks running on it. This demands keeping a task database in the worker’s memory and updating it every time a task change’s state. The worker also needs to be able to provide information about its resources, like the available CPU and memory. The book suggests reading the /proc Linux file system using goprocinfo, but since I use a Mac, I used gopsutil. The manager On top of our cluster of workers, we have the manager. The manager also exposes an API, which allows us to start, stop, and list tasks on the cluster. Every time we want to create a new task, the manager will call a scheduler component. The scheduler has to list the workers that can accept more tasks, assign them a score by suitability and return the best one. When this is done, the manager will send the work to be done using the worker’s API. In the book, the author also suggests that the manager component should keep track of every tasks state by performing regular health checks. Health checks typically consist of querying an HTTP endpoint (i.e. /ready) and checking if it returns 200. In case a health check fails, the manager asks the worker to restart the task. I’m not sure if I agree with this idea. This could lead to the manager and worker having differing opinions about a task state. It will also cause scaling issues: the manager workload will have to grow linearly as we add tasks, and not just when we add workers. As far as I know, in Kubernetes, Kubelet (the equivalent of the worker here) is responsible for performing health checks. The CLI The last part of the project is to create a CLI to make sure our new orchestrator can be used without having to resort to firing up curl. The CLI needs to implement the following features: start a worker start a manager run a task in the cluster stop a task get the task status get the worker node status Using cobra makes this part fairly straightforward. It lets you create very modern feeling command-line apps, with properly formatted help commands and easy argument parsing. Once this is done, we almost have a fully functional orchestrator. We just need to add authentication. And maybe some kind of DaemonSet implementation would be nice. And a way to handle mounting volumes…
Email is your most important online account, so keep it clean.
As I slowly but surely work towards the next release of my setcmd project for the Amiga (see the 68k branch for the gory details and my total noob-like C flailing around), I’ve made heavy use of documentation in the AmigaGuide format. Despite it’s age, it’s a great Amiga-native format and there’s a wealth of great information out there for things like the C API, as well as language guides and tutorials for tools like the Installer utility - and the AmigaGuide markup syntax itself. The only snag is, I had to have access to an Amiga (real or emulated), or install one of the various viewer programs on my laptops. Because like many, I spend a lot of time in a web browser and occasionally want to check something on my mobile phone, this is less than convenient. Fortunately, there’s a great AmigaGuideJS online viewer which renders AmigaGuide format documents using Javascript. I’ve started building up a collection of useful developer guides and other files in my own reference library so that I can access this documentation whenever I’m not at my Amiga or am coding in my “modern” dev environment. It’s really just for my own personal use, but I’ll be adding to it whenever I come across a useful piece of documentation so I hope it’s of some use to others as well! And on a related note, I now have a “unified” code-base so that SetCmd now builds and runs on 68k-based OS 3.x systems as well as OS 4.x PPC systems like my X5000. I need to: Tidy up my code and fix all the “TODO” stuff Update the Installer to run on OS 3.x systems Update the documentation Build a new package and upload to Aminet/OS4Depot Hopefully I’ll get that done in the next month or so. With the pressures of work and family life (and my other hobbies), progress has been a lot slower these last few years but I’m still really enjoying working on Amiga code and it’s great to have a fun personal project that’s there for me whenever I want to hack away at something for the sheer hell of it. I’ve learned a lot along the way and the AmigaOS is still an absolute joy to develop for. I even brought my X5000 to the most recent Kickstart Amiga User Group BBQ/meetup and had a fun day working on the code with fellow Amigans and enjoying some classic gaming & demos - there was also a MorphOS machine there, which I think will be my next target as the codebase is slowly becoming more portable. Just got to find some room in the “retro cave” now… This stuff is addictive :)
One of the first types we learn about is the boolean. It's pretty natural to use, because boolean logic underpins much of modern computing. And yet, it's one of the types we should probably be using a lot less of. In almost every single instance when you use a boolean, it should be something else. The trick is figuring out what "something else" is. Doing this is worth the effort. It tells you a lot about your system, and it will improve your design (even if you end up using a boolean). There are a few possible types that come up often, hiding as booleans. Let's take a look at each of these, as well as the case where using a boolean does make sense. This isn't exhaustive—[1]there are surely other types that can make sense, too. Datetimes A lot of boolean data is representing a temporal event having happened. For example, websites often have you confirm your email. This may be stored as a boolean column, is_confirmed, in the database. It makes a lot of sense. But, you're throwing away data: when the confirmation happened. You can instead store when the user confirmed their email in a nullable column. You can still get the same information by checking whether the column is null. But you also get richer data for other purposes. Maybe you find out down the road that there was a bug in your confirmation process. You can use these timestamps to check which users would be affected by that, based on when their confirmation was stored. This is the one I've seen discussed the most of all these. We run into it with almost every database we design, after all. You can detect it by asking if an action has to occur for the boolean to change values, and if values can only change one time. If you have both of these, then it really looks like it is a datetime being transformed into a boolean. Store the datetime! Enums Much of the remaining boolean data indicates either what type something is, or its status. Is a user an admin or not? Check the is_admin column! Did that job fail? Check the failed column! Is the user allowed to take this action? Return a boolean for that, yes or no! These usually make more sense as an enum. Consider the admin case: this is really a user role, and you should have an enum for it. If it's a boolean, you're going to eventually need more columns, and you'll keep adding on other statuses. Oh, we had users and admins, but now we also need guest users and we need super-admins. With an enum, you can add those easily. enum UserRole { User, Admin, Guest, SuperAdmin, } And then you can usually use your tooling to make sure that all the new cases are covered in your code. With a boolean, you have to add more booleans, and then you have to make sure you find all the places where the old booleans were used and make sure they handle these new cases, too. Enums help you avoid these bugs. Job status is one that's pretty clearly an enum as well. If you use booleans, you'll have is_failed, is_started, is_queued, and on and on. Or you could just have one single field, status, which is an enum with the various statuses. (Note, though, that you probably do want timestamp fields for each of these events—but you're still best having the status stored explicitly as well.) This begins to resemble a state machine once you store the status, and it means that you can make much cleaner code and analyze things along state transition lines. And it's not just for storing in a database, either. If you're checking a user's permissions, you often return a boolean for that. fn check_permissions(user: User) -> bool { false // no one is allowed to do anything i guess } In this case, true means the user can do it and false means they can't. Usually. I think. But you can really start to have doubts here, and with any boolean, because the application logic meaning of the value cannot be inferred from the type. Instead, this can be represented as an enum, even when there are just two choices. enum PermissionCheck { Allowed, NotPermitted(reason: String), } As a bonus, though, if you use an enum? You can end up with richer information, like returning a reason for a permission check failing. And you are safe for future expansions of the enum, just like with roles. You can detect when something should be an enum a proliferation of booleans which are mutually exclusive or depend on one another. You'll see multiple columns which are all changed at the same time. Or you'll see a boolean which is returned and used for a long time. It's important to use enums here to keep your program maintainable and understandable. Conditionals But when should we use a boolean? I've mainly run into one case where it makes sense: when you're (temporarily) storing the result of a conditional expression for evaluation. This is in some ways an optimization, either for the computer (reuse a variable[2]) or for the programmer (make it more comprehensible by giving a name to a big conditional) by storing an intermediate value. Here's a contrived example where using a boolean as an intermediate value. fn calculate_user_data(user: User, records: RecordStore) { // this would be some nice long conditional, // but I don't have one. So variables it is! let user_can_do_this: bool = (a && b) && (c || !d); if user_can_do_this && records.ready() { // do the thing } else if user_can_do_this && records.in_progress() { // do another thing } else { // and something else! } } But even here in this contrived example, some enums would make more sense. I'd keep the boolean, probably, simply to give a name to what we're calculating. But the rest of it should be a match on an enum! * * * Sure, not every boolean should go away. There's probably no single rule in software design that is always true. But, we should be paying a lot more attention to booleans. They're sneaky. They feel like they make sense for our data, but they make sense for our logic. The data is usually something different underneath. By storing a boolean as our data, we're coupling that data tightly to our application logic. Instead, we should remain critical and ask what data the boolean depends on, and should we maybe store that instead? It comes easier with practice. Really, all good design does. A little thinking up front saves you a lot of time in the long run. I know that using an em-dash is treated as a sign of using LLMs. LLMs are never used for my writing. I just really like em-dashes and have a dedicated key for them on one of my keyboard layers. ↩ This one is probably best left to the compiler. ↩
