Search Results: "phil"

14 October 2026

Dirk Eddelbuettel: qlcal 0.1.4 on CRAN: Fresh Upstream Updates

The twenty-second release of the qlcal package arrivied at CRAN yesterday, and has been built for r2u as well as on r-universe. qlcal delivers the calendaring parts of QuantLib. It is provided (for the R package) as a set of included files, so the package is self-contained and does not depend on an external QuantLib library (which can be demanding to build). qlcal covers over seventy country / market calendars and can compute holiday lists, its complement (i.e. business day lists) and much more. Examples are in the README at the repository, the package page, and course at the CRAN package page. This release is based on the changes in the QuantLib 1.44 release also made yesterday. It includes two new calendars for Malaysia and the Philippines, updates to around a dozen calendars, and a few other updates to internal files. Maxmilian Muecke spotted and fixed a few small bugs just as he did for the RQuantLib release we made yesterday; this is equally appreciated! The full details from NEWS.Rd follow.

Changes in version 0.1.4 (2026-10-13)
  • Add missing market calendars for Poland, Russia, Romania, Indonesia (Maximilian Muecke in #21)
  • Add (semi-deprecated) alternate separators '::' for Israel and New Zealand markets (Maximilian Muecke in #22)
  • Fix several typos across source, configuration and documentation files (Maximilian Muecke in #23)
  • Synchronize with QuantLib 1.44, add two new calendars, update several others, and update general utility files (Dirk in #24)

Courtesy of my CRANberries, there is a diffstat report for this release. See the project page and package documentation for more details, and more examples.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. If you like this or other open-source work I do, you can sponsor me at GitHub.

13 October 2026

Dirk Eddelbuettel: RQuantLib 0.4.29 on CRAN: New QuantLib, Plus Small Fixes

A new release 0.4.29 of RQuantLib arrived on CRAN this evening, had already been built for r2u as well as on r-universe and has just been uploaded to Debian. QuantLib is a rather comprehensice free/open-source library for quantitative finance. RQuantLib connects (some parts of) it to the R environment and language, and has been part of CRAN for twenty-three years (!!) as it was one of the first packages I uploaded to CRAN. This release of RQuantLib brings two new calendars (Malaysia, Philippines), updates to a number of other calendars as well to other files, and two deprecations we are reflecting in this release. It also benefits from a number of careful and attentive pull requests by Maximilian Muecke cleaning up an (astonishing !!) number of likely rather old little bugs. Full details from the NEWS file follow as usual.

Changes in RQuantLib version 0.4.29 (2026-10-13)
  • Configure check for outdated QuantLib version updated,
  • Adjust two instantiations on macOS x86_64 with old compilers
  • Correct Euribor2W and Euribor3W tenors setters (Maximilian Muecke in #196)
  • Accect Euribor1W as alias for EuriborSW tenor (Maximilian Muecke in #197)
  • Correct default handling of the payFixed parameter (Maximilian Muecke in #198)
  • Assign missing S3 class to American option implied volatitly return (Maximilian Muecke in #199)
  • Correct spelling in manual pages and R code (Maximilian Muecke in #202, #203)
  • Support additional Polish settlements (Maximilian Muecke in #204)
  • Check for curve parameters in FittedBondCurve (Dirk in #205 fixing #201)
  • Reflect two deprecations in QuantLib 1.44 and adjust code in two spot (Dirk in #206)

Courtesy of my CRANberries, there is also a diffstat report for the this release. As always, more detailed information is on the RQuantLib page. Questions, comments etc should go to the rquantlib-devel mailing list. Issue tickets can be filed at the GitHub repo.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. If you like this or other open-source work I do, you can now sponsor me at GitHub.

9 October 2026

Louis-Philippe V ronneau: Removing myself as a Lintian uploader in the next few weeks

A few days ago, a colleague reached out to me, asking if I could help draft a resolution on digital autonomy and free software for the upcoming renewal of our collective bargaining agreement. Although she's very politicised and generally a great individual, she is not a techie and we never really talked about these issues before. This took me by surprise. I should have been rejoicing; no, I should have been the one who brought up this topic in our union. Wasn't I the technical expert on these issues? But alas, my first reaction when she came to me was to snicker and tell myself: "That's cute, but nothing's ever gonna change, Big Tech is too strong and our governments don't give a damn." How sad and cynical is that? That's not the person I want to be. Something in the Quebecois political landscape has shifted in the last few years with regards to tech. More and more "regular" people seem to be talking about the importance of digital autonomy, how government services shouldn't rely on Big Tech and how we should be using FOSS on hardware we actually control. A few years ago, I would have been at the vanguard of this change. I would have been part of the creation of Donn es souveraines Qu bec. Heck, they are organising a whole conference next week and I'm not even going. How did this happen to me? I first fell for Free Software for its political ideals: Knowledge Should Be Free, Cooperation Is More Efficient Than Competition, Centralisation Should Be Avoided When Possible, etc. I still believe in all of this, but somehow, after years of fighting for change in the tech world, I have retreated into technical work. I maintain Debian packages as a hobby and to scratch my own itch. I run services for myself and a few friends. I organise Debian User Group meetings. To be clear, I haven't generally given up. I'm very politically active in my union and at work, I'm a good member of my housing cooperative and I'm still fighting against the industrialisation of natural spaces in my neighborhood. But when it comes time to defend freedom in the tech world, lately, I've just been shrugging and accepting I should use Microsoft Teams like every one else does. I want this to change and to do so, I need to free some time. Lintian Two years ago, I added myself to Lintian's Uploaders list. Up until then1, I enjoyed fixing little issues here and there and liked creating new tags to help out the Python Team, where most of my Debian time was spent. Lintian was badly in need of a new maintainer and as I felt it was an important project, I decided to step in. 37 releases and about 160 closed bugs later2, I'm done. To be honest, I haven't had much fun maintaining Lintian lately. Bugs keep piling on the BTS, so much so I have mostly been ignoring them for the past few months. In fact, most of the actual work triaging, writing code and fixing bug has been done by Nilesh Patra for a while now. All this to say, if you care about Lintian, you should consider adding yourself to the Uploaders list, as I'm out and Nilesh can't do all the work by himself. He's a great person to work with and since I don't want to suddenly leave him all alone, I'll be sticking around for a few more weeks in the hope someone else will volunteer to help out. A smooth transition with a new co-maintainer would really be nice! If you're interested, don't hesitate to reach out to me on IRC or by email.

  1. My first technical commit to Lintian was nearly 7 years ago! Crazy how time flies.
  2. Mostly closed by other people than I!

27 September 2026

Russ Allbery: Review: Ode to the Half-Broken

Review: Ode to the Half-Broken, by Suzanne Palmer
Publisher: DAW
Copyright: May 2026
ISBN: 0-7564-2013-X
Format: Kindle
Pages: 441
Ode to the Half-Broken is a standalone post-apocalyptic (sort of) science fiction novel. As this novel opens, the unnamed first-person protagonist is waking up in a bathtub in an abandoned building. They are covered in electromagnets and missing one leg. Waking up involved a secure reboot from a protected core kernel, so it is immediately obvious that the protagonist is a robot. That also explains the electromagnets, which interfere with their ability to control their body. Or they would, if the protagonist didn't have long-dormant combat routines available to deploy EM shielding and free themselves from the bathtub. There are no immediate answers to why someone embedded a virus in the data attached to a scientific paper on ants, an act so precisely targeted that it had to be personal. Or what happened to their leg.
"There are a number of electromagnets in the next room," I say. I point. "Behind that wall with all the holes in it." "Those are big holes. And fresh, too," the dog says. "I wonder what made them." "Electromagnets experiencing sudden velocity." The dog gives another of its short barks, and I am more convinced now it is laughing, though I was not attempting to be funny.
Ode to the Half-Broken has a classic science fiction beginning: in medias res in a future science fiction version of Earth where nothing is immediately explained, leaving the reader to work out the date and the setting. Helping us out is the protagonist, who is neither chatty nor very sociable with other characters but keeps up an analytical monologue about the world as they narrate events. We are some decades into a grim future. The United States has largely collapsed. Large parts of New York City are dangerous to humans due to disease and radiation. Neither of those hazards bother the large number of sentient robots; their scarcity, and therefore economy, is instead based on power. Robots that control solar power stations act as low-level mob bosses, trading power for information or labor. Our protagonist doesn't want to care about any of this. They retreated from the world long ago for a solitary life in the former New York Botanical Gardens studying ants. But they need a new leg and the best robot repair person nearby is a human woman outside of the city, so they reluctantly head in that direction, accompanied somewhat surprisingly by a cyborg dog. The typical science fiction apocalypse is caused by something specific. Classically, that event is a nuclear war, but writers found various alternatives before, during, and after the Cold War era: alien invasions, meteor showers, plagues, sea level rise, and peak oil and general environmental collapse, among many others. Less common is a post-apocalyptic novel where the collapse comes from multiple overlapping crises and accumulating failures, from a general failure to meet what Adam Tooze and others call polycrisis. The first time I encountered that style of post-apocalyptic story was in Octavia Butler's Parable of the Sower. It was one of the choices that made (and still makes) that book feel so chillingly realistic. The world background in Ode to the Half-Broken is shaped by that sort of polycrisis collapse. There is no one reason why New York City is a dangerous, irradiated ruin and society has collapsed into isolated and sometimes warring factions. It is not runaway artificial intelligence, or at least not directly; sentient robots were a late-stage innovation of the collapsing US civilization and a tool and accelerator of its many wars, but they were not the cause and may be a critical ingredient in building some functional replacement. Instead, society fell apart because we failed to address any of the growing problems and then turned on each other in the resulting ruins. The reader gets an idiosyncratic view of that collapse in flashback chapters intermixed with the main narrative of the initially unnamed robot protagonist, flashbacks told from the perspective of the man who invented the key component for robot sentience. As you would expect, those two narratives are linked. The reader will not discover how they are linked until late in the story. This book could have been extremely depressing. It is not, which says a great deal about Palmer's skill in telling it. The clinical distance of the protagonist in the early chapters helps considerably: They have rejected involvement in this world and therefore can describe it in detached, factual terms, aided by the tendency of most robots in this story to be slightly more precise, logical, and verbose than the human characters. But as the protagonist's clinical distance fades, as it must to allow the story's emotional stakes to rise, Palmer fills this book with moments of beauty and hope. A former nuclear submarine that has become the mind of a subway car is a key early ally. A collective has turned the Hudson Bridge into a thriving if chaotic community. Self-regulating enclaves of humans and robots are working together to try to build a livable world. Robots oversee pollinator swarms that are attempting to restore plant life, for no reason other than that they like order and stability and see this as a way of restoring both. This is a grim, post-apocalyptic world that does not dwell on either the grimness or the apocalypse. It is instead full of small moments of hope, collaboration, and personal connection. This is a story with villains, danger, pain, and risk. Despite the similar keywords and cover aesthetics, it bears little resemblance to Becky Chambers's philosophical Monk and Robot series. It is not, in any definition of the term, cozy; it's a post-apocalyptic adventure story about a robot and a dog making their way through a ruined civilization and fighting people who are trying to build something even worse on the rubble. But it's also charming and oddly happy. There are strong found-family vibes in the way that a party coalesces around the protagonist and eventually gives them a name, there is the quiet happiness of seeing a grumpy misanthrope slowly come out of their protective shell, and the rail mechs are an absolute delight. Like a lot of stories of happy small-group anarchism, I didn't entirely believe the politics and have some qualms about the realism of the ending, although perhaps I should strive to be as optimistic as Palmer writes. The somewhat dry and fussily precise first-person narration will also not be to everyone's taste; it worked for me by the end of the book, but it took a bit of reading to get used to it. But those quibbles aside, this was quietly lovely. It's a satisfying science fiction adventure story in a world with disturbing parallels to the one we're living in, but which uses those parallels to focus on small-scale collective efforts to build something better. And all the small details of the world-building are delightful: the different tiers of robots and their odd behaviors, the machine sense of purpose, even the mix of suspicion and generosity. The plot has large-scale implications, but it was the human-level details that charmed me. I still want another Fergus novel, but this was a highly successful foray outside of that series. Palmer has won two Hugos for her novellas, so I can't really say she's overlooked, but her novels aren't getting anywhere near the attention they deserve. Highly recommended. There is plenty of world-building room here for a sequel, but Ode to the Half-Broken reaches a satisfying standalone conclusion. So far as I know, no sequel is currently planned. Rating: 8 out of 10

18 September 2026

Paul Tagliamonte: Why Write?

As a graduate of a liberal arts university, I wound up, unsurprisingly, taking a lot of classes in every possible academic discipline. Thinking back to the person that I was going into university, I don t think I would have chosen to take them after all, my degree was in the sciences; I d have been stoked to do nothing more than wall-to-wall computer science until I ran out of coursework and filled the rest of my hours with research and independent studies with my professors (which, I guess I did actually do, just not as much as I would have otherwise). Even this blog s CSS theme (now 18 years old and starting to look it) was something I wrote after receiving and repeatedly re-reading a tattered third-hand copy of The Laws of Thought by George Boole. It was gifted to me by a college friend majoring in philosophy while I was crashing at his rental on the beach. He gave it to me because he knew I liked that shit and, while it was definitely computer science in nature, I would not have read it otherwise. I have vivid memories of sleeping on his la-z-boy surrounded by towers of books he was working through. He went on to do incredible work, getting his PhD, doing research, brilliant writing his death in 2023 has robbed humanity of more time with him. The Laws of Thought sits behind me in my office, and is one of my most valued possessions. My friends mean more to me than I could ever express, and I definitely don t show it enough. Each of my classes made me a more thoughtful person. My professors made me a better, more well-rounded person and a person who attempts to live up to the oft repeated credo of being men and women for others . I did the best I could, even though I was never a particularly good student. Without liberal arts, I don t think I would, dispositionally, have been capable of pushing myself to this day to continue to learn on nights and weekends, for no reason other than wanting to learn. I refuse to stop expanding my perspective, and do my best to approach new problems with as much humility and curiosity as I can muster. Every few days for the last year or so, I have been thinking back to a reading assignment from my junior year that, at the time, I thought was a borderline throwaway filler assignment for the class. The reading is an essay from 1947 by the french existentialist philosopher and libertarian marxist, Jean-Paul Sartre (as some of the more erudite may have now already worked out given the blog s title), Why Write? . I re-read it this week. It is not filler. I remember this essay better than some of the classwork I considered more important at the time.

Why Write? Why Write? starts off by describing the ways in which writing trying to communicate your thoughts, opinions, or feelings to others is an act of projection. The writer will only ever draw from a place of their own subjectivity writing is taking your person and putting it on display. You re choosing what words to use, how to use them, pulling from knowledge you ve accumulated (based on how you ve chosen to spend your time). Spending any amount of your finite existence in order to convey a thought is, itself, announcing to the world that you believe it to be a thought worth sharing. Meanwhile, the act of reading is not simply turning letters into words. Reading is engaging with the work, and understanding the work in a process that looks more like what Sartre terms re-invention or discovery the literary object, though realized through language, is never given in language . It is not enough to read the words in a book end-to-end; you must, as a reader, actively engage with the work to understand what is being communicated by those words. Reading is to take the words on the page, and exceed the mere words through what he calls directed creation . The reader is re-inventing / discovering the writer s thoughts by following their landmarks in the void . And this all makes pretty good sense to me I know if someone is being sarcastic because I know the writer; I have read their words and have read into their words, allowing myself to be directed by the writer into discovering the thought they have left me in their work. I understand that their words are humorous, not irate. Knowing who the author of a work is can completely change the point of a sentence. The fact I m writing about Sartre at all, or that this very writing has been constrained for presentation in this blog s CSS is only happening because of who I am, what things I ve experienced in life, and what has made me, me. Sartre argues that this dyadic coupling between writer and writing means that I, as a writer, can never truly read my own writing. I will never be capable of reading my own work and getting something out of it the work is already an extension of my own person. I can discover no thought in my own works. Of course, Sartre, as an existentialist, is honor bound to go one step further here the reader, by participating in reading a work, is asserting their own freedom. Every time a writer writes [ ] the writer appeals to the reader s freedom to collaborate in the production of [their] work . The creative act may only be complete if both writer and reader have recognized one another and made a choice to do so. No one is compelled to complete the creative act. The things you read matter. Reading something fundamentally alters you as a person you can not simply un-read a thought. Everything you read changes your universe. I have a hunch Sartre would find things like the (original early 2010s era) tl;dr reply to obviously terrible writing absolutely hilarious as a reader s expression of freedom (not to be confused with modern 2020s era usage as shorthand for summary section ). Using your freedom to choose to complete the writer s creative act (or not) is inherently asserting your humanity. I m a bit fuzzy on the specifics of this quote, but I think it was sj who told me at one year s Mystery Hunt that A puzzle is a contract between puzzle author and puzzle solver, the author promises that the puzzle is solvable if you re clever enough . The puzzle author and puzzle solver are engaging in a collaborative production of the work that is only possible by recognizing one another. Similarly, Sartre whatever connections [the reader] may establish among the different parts of the book among the chapters or the words [the reader] has a guarantee, namely, that they have been expressly willed .

Wall Drawing #123 It follows, Sartre argues, that the act of writing, as a means to convey a thought to a reader, may only be completed through the act of reading. Reading can only be done by others; writing, therefore, only exists to be read it can serve no other purpose. Writing and reading are two halves of the same creative, collaborative act, only satisfied when both writer and reader acknowledge one another. Combined, writing and reading are the act of recognizing one another s humanity, thoughts, experiences, consciousness the act of co-creation of thought is the critical aspect of writing and reading reconstructing the author s perspective, thought, intent, point. The co-creation is the point of both reading and writing. Writing without anyone to read the work leaves the writer s bid for co-creation unsatisfied and humanity unrecognized. No thought has been conveyed to any reader, no one has understood the reason behind the landmarks in the void you ve carefully placed, leaving you to either [ ] put down [your] pen or despair . Writing is an appeal to the reader s freedom, and the nature of that freedom is the writer can not control it never being understood is always a possibility any time anyone sets out to write. Nearly 12 years ago, I attempted to read the text on the git manpage generator for the first time I remember the exact feeling of my brain going into git manpage parsing mode where every word was dragging git plumbing megaliths through the sand from their far-flung homes. I can still feel the surface of my desk as I instinctually started to trace out logical connections between git internals referenced as I read along. It took me a good 20 seconds to realize what I was reading made no sense. This website broke Sartre s writer-reader agreement I was attempting to read this website, but there was nothing there. You can mechanically read the git-man-page-generator, but you can never read it it is not possible to read it. It was funny unsettling. Each grasp at a real-looking image in front of me misses, my hand coming back empty. I couldn t get enough of it. I must have tried to read a dozen generations in a row. I had never had something quite that broken pass that far into my consciousness before. Although I kept trying, it never did feel quite the same as that first time; I think fundamentally, I couldn t forget that it was random. While never having anyone read your writing drives them to put down your pen or despair , Sartre never had to contend with the opposite problem being asked to read that which was not written. Reading that which was not written does not merely leave someone unrecognized when a reader makes a choice; instead, it is an inherent violation of the contract between reader and writer. Not only is no humanity being recognized through attempting to read words which were not written, but the reader, not the writer, is the one who bears the burden of unexpected apophenia. The reader, while engaging in co-creation, must now contort themselves to uphold their end of the Sartrean agreement, scrutinizing text to ascribe consciousness, thought and intent only to come back up with pareidolia-fueled echos of one s own self and disfigured half-thoughts of others. The reality is, the modern reader must now mechanically read most written work they come across, scrutinizing text for any signs of thought before truly attempting to read the work. Failing to do this correctly changes our person each time it happens, a small part of us is irrevocably altered. Choosing to engage in this ballet because you wish to do so is one thing this is your right and freedom as a reader but passing words which were not written as your own in an attempt to wrestle a reader s freedom of co-creation from them is another entirely. If you didn t write it, I don t want to read it (dw;dr). Send me your prompt instead.

Petter Reinholdtsen: Long term storage of Mattermost messages with Noark 5 XML

It is said that those who cannot remember the past are condemned to repeat it, a quote often attributed to the American philosopher George Santayana. And to remember the past, records must be maintained and kept accessible to learn from. With this in mind, it is no wonder that archivists worldwide consider it crucial to ensure the archival records are both complete and accurate, with a constant frustration caused by the knowledge that the archives are neither due to challenges in tracking down and collecting what should be archived. The last few days, I decided to simplify the collection of Messages from the Mattermost chat service, used by a few of the organisations I am involved in, to try to improve the situation slightly. To achieve this, I had written a dedicated extraction tool. Partly to see how hard it would be, and partly to ensure that if one of the services were shut down or replaced, everything in it would not be lost. Of course it is in the nature of the use of instant messages that most of them are not fit for permanent storage, at least not according to Norwegian law, where there is a threshold "worthy of the archive" (arkivverdig) that should be met, and messages like "should we go to lunch now" are below the bar and should be filtered out. The tool can not help with this filtering, and that will have to be done using other means after collection. The tools I had my bullshit generator write, under strict supervision and many iterations, will extract every message visible to the user whose credentials are used to log into Mattermost, and write it out in Noark 5 extraction XML format and visualize the result. I created the visualiser mostly to quickly be able to debug the extracted XML, but also to make life easier for anyone interested in testing out the tool set. The extractor mattermost-noark5extract create a hierarchy with arkiv/arkivdel for the Mattermost server, and then individual mappe for each channel and direct message chat, a registrering for each message thread, dokumentbeskrivelse for every message in the tread, and one or more dokumentobjekt for each message and their attachments/images. So far it is only tested on one Mattermost installation, where around 23,000 messages is extracted in 61 seconds and produce 295M with approximately 600 attachments and around 675,000 lines of XML in arkivstruktur.xml. You pass it the URL of the service, a username and password, a directory path where to store the collection and an optional channel name substring to limit the collection to only a subset of the messages available. The mattermost-noark5extract-browser viewer can load this collection and visualize it similarly to Mattermost's web interface, with the list of channels and direct messages dialogues on the left, messages chronologically in the centre and a selected thread displayed on the right. I know Mattermost provide several login options. I've only had the one used on my test server implemented so far, and know the extract tool will have to be extended a bit for it to handle servers using one of these options. If you would like to examine the new toolkit, mattermost-noark5extract is available from gitlab. I wanted to put it on codeberg, but as the recent rule change forbid code mostly written by a bullshit generator there, it was not really an option. Note that some years ago I wrote a similar tool to extract material from the request tracker system. The source for request-tracker-noark5extract is also available from codeberg. I would love to hear from you if you test the tools. As usual, if you use Bitcoin and wish to support my activities, please send donations to 15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b.

Louis-Philippe V ronneau: Fake Cash: The World Trade Game

This is a new series1 I'm starting on the tools I have been crafting and buying to play pedagogical games in my Economics classes. These games, aside from being just plain fun for the students, often aim to teach them a lesson via interactive play. Unsurprisingly, it is much easier for them to grok a particular concept this way. Moreover, many students told me these activities were the best part of the classes I teach. The World Trade Game I found out about The World Trade Game in The Handbook of Pluralist Economics Education2, which also contains many other fun pedagogical games. It was first developed by Action Aid, but has since been refined by John Sloman and then by Irene van Staveren, who wrote about her use of the game in the aforementioned book. The goal of this blog entry is not to describe the game and teach you how to play it. If that interests you, either buy the book I mentioned or read about Sloman's version here. No, our focus point here is the tools to play this game: fake cash! Fake cash can be used in many economics pedagogical games and in my opinion, is a worthwhile "investment" of your time and energy. You could indeed play with regular printed sheets of paper listing a value (I sure did!), but using Play Money (a more appropriate term, since we're not trying to defraud anyone) will up your game and create a more immersive atmosphere in your classes. At first, I tried to buy play money. Surely, some commercial offering aiming to create realistic props for movies and TV productions existed? At least in Canada, it turns out the answer was no. The only thing I could find were shady websites and weird expensive listings on AliExpress. Not being tenured yet, I did not try to convince my employer to take a 50-50 chance on supporting criminal endeavours. As such, the next best thing I found was printable play money designed by the Bank of Canada Museum. Their designs were quite nice and met my needs, but their PDF layout made it overly complicated to print large quantities of bills. As such, I played around with GIMP a little and came out with these files. A commercial printer shouldn't have issues printing them on glossy cardstock paper and cutting them up for you: Once printed and cut, you'll unfortunately have to fold each bill by hand. To secure both halves, I ended up using a strip of transparent tape on each long edge. Here is the result, with a real Canadian 20$ bill as a comparison: Stacks of play money bills, with examples of the 5$, 10$, 20$, 50$ and 100$ bills A real Canadian 20$ bill, side-to-side with the play money version

  1. Don't hold your breath though, as I do not currently have a release schedule.
  2. Reardon, J. (2009). The Handbook of Pluralist Economic Education. New York : Routledge.

4 August 2026

Anuradha Weeraman: Plan 9 from Bell Labs, the little OS that could

Plan 9 Fourth Edition showing the rio windowing systemScreenshot by VulcanSphere via Wikimedia Commons MIT License
I first heard of Plan 9 from my friend Vajra in 1999 or so, as we were distro-hopping on early Linux distributions and trying to find our way. Vajra is now a Nebula Award-winning science fiction author - have a look at his work. We had just been through Tom's Root Boot, a UNIX-like operating system crammed into a single floppy, and through it discovered a whole new world outside of DOS 6.22. Combing through old UNIX manuals, we went in search of the perfect OS, through Slackware, Caldera, TurboLinux, SUSE and Red Hat. I finally settled on Debian, which lived up to everything I stood for. Plan 9 was distinct. It came out of the Computing Sciences Research Center at Bell Labs, built by Rob Pike, Ken Thompson, Dave Presotto and Phil Winterbottom, with Dennis Ritchie heading the department. The name is a joke at their own expense, borrowed from Ed Wood's 1959 Plan 9 from Outer Space, routinely nominated as the worst film ever made. Thompson and Ritchie had, of course, built the original UNIX; it almost seemed as if they were building a new OS from the lessons learnt from building it - which was in turn built on the lessons from Multics. I remember the awe I felt playing around with Plan 9, and I've not been able to replicate it since. Plan 9 was different in a couple of fundamental ways: per-process namespaces, and a protocol that abstracted locality of resources to processes. As a consequence of these core primitives, the OS surface area was distinctly small. The entire system from the core kernel, to the system call interface, to the compiler, linker and shell was reduced to a form small enough that a single developer could hold it in their head. Lessons from the implementation of UNIX helped the designers make the system leaner, and in Ken Thompson's words, it's the "best operating system out except that it doesn't have the apps that everybody demands" [1]. It also took the concept of "everything is a file" in UNIX to a whole new level. The network stack is a filesystem (/net), processes are files, the display is a file (/dev/draw). Because every resource speaks 9P and every process has its own namespace, you can mount another machine's /net into your namespace and your program makes network calls through that machine's stack without knowing or caring. No sockets API, no RPC layer, just ordinary file system operations through a simple system call interface. Some would say that OS research is dead, and that backwards-compatibility and POSIX killed it. Rob Pike himself argued as much in his 2000 talk, "Systems Software Research is Irrelevant" - but we didn't care at the time. There was so much happening that we didn't have time to take it all in. And then Linux happened, and Software Freedom became a focal point (more on that in a later post). In the summer of 2020, with the world deep in Covid lockdowns, I decided to build a toy operating system, just to try my hand at the the thing that I had always wanted to do. I spent three feverish months working on Odyssey and, looking back, it is perhaps the most fun I have ever had. I would not dare compare it to the magnum opus that is Plan 9, but it gave me perspective: how hard it is to build an OS from scratch, and above all, how fun it is to build an OS from scratch, and why the original creators kept coming back to the same problem. The highlight of those three months was booting the OS and watching it render "The Great Wave off Kanagawa". Nothing in my professional achievements to date captures what that meant to me.
Odyssey rendering The Great Wave off Kanagawa during boot Odyssey displaying "The Great Wave Off Kanagawa"
Decades on from the first time I booted Plan 9, I look back with nothing but awe and respect for the creators of this little operating system and marvel at the foresight that went into it. While many readers will not have heard of Plan 9, they have almost certainly worked with the ideas that came from it: 9P (if you ever used the Windows Subsystem for Linux), UTF-8 (if you ever used any modern operating system), per-process namespaces (if you've ever run a container), Go (whose assembler still uses Plan 9 syntax). Plan 9 still lives on in 9front, a community-maintained fork. Separately, Yoann Padioleau [2] has produced a set of annotated books at principia-softwarica.org, presenting the Plan 9 source in the spirit of Donald Knuth's literate programming - an admirable effort to introduce new readers to the art of operating systems engineering. Pike thought systems research had become irrelevant, and Thompson thought Plan 9 would never "make it" [1]. Both were right about the industry, but may have been pessimistic about the impact. The system lost as a product but won as a set of ideas, assimilated one at a time by modern operating systems. Success is not always measured by popularity. The mark that Plan 9 left behind is greater than what's reflected in its current user base. To me, Plan 9 will always be the OS that punched above its weight class, the little OS that could. References [1] Ken Thompson Interview, March 6, 2024 [2] Yoann Padioleau Principia Softwarica, May 9, 2026

1 August 2026

Russ Allbery: Review: How to Steal a Galaxy

Review: How to Steal a Galaxy, by Beth Revis
Series: Chaotic Orbits #2
Publisher: DAW Books
Copyright: December 2024
ISBN: 0-7564-1949-2
Format: Kindle
Pages: 143
How to Steal a Galaxy is a far-future science fiction caper short novel (maybe a novella?) and the sequel to Full Speed to a Crash Landing. You don't have to remember the details of the previous book to enjoy this one. There's an excellent inline summary at the start of this installment. After an annoying negotiation with people who keep trying to preach at her about causes, Ada Lamarr has a new contract. She is going undercover, after a fashion, at a charity gala and auction on Rigel-Earth. While she's there, she's going to steal something. What, precisely, she keeps a mystery from both the other characters and from the reader until the end of the story. Government agent Rian White is working security at this charity gala. Due to its link with the plot of Full Speed to a Crash Landing, he was fairly certain Ada would be there, as indeed she is. What she is planning, however, is maddeningly unclear. Also maddening is how good Ada looks in a dress. As with the previous book, How to Steal a Galaxy is told by Ada in the first person using the same teasing tone and constant misdirection that she uses when verbally fencing with Rian and the other characters. I found this novella even more entertaining and satisfying than the previous one. The charity gala is supposedly intended to benefit the poor people of Earth, and is run with exactly the sort of condescension and disguised capitalist looting typical of such exercises in elite charity. Ada's narration is scathing in a deeply relatable way. Also, there is a trillionaire tech-bro fake philanthropist who is smug and condescending and accustomed to getting exactly what he wants.
"I don't think anyone should have enough personal wealth to decimate a large country's income just because he's going through a midlife crisis."
Ada's interactions with Strom Fetor are an absolute delight. He is so sure of himself that he is incapable of registering her as a threat, and she effortlessly deceives him by hiding in plain sight.
"You really shouldn't be talking about this," Rian starts. Fetor waves aside his concerns. "We're all friends here." "Not me," I say. "I hate you. Remember?" Fetor laughs in a tone I'm sure he thinks is charming.
Fetor's complete inability to realize that a beautiful woman might both sincerely not like him and not be flirting with him is perfect. I was cackling through half of this book. Like any good heist story, there are twists and turns, surprises, double agents, unexpected complications, and a delightful amount of verbal fencing. I adore the narrative tone Revis uses for these stories. Ada has just the right mix of idealism, cynicism, professionalism, and irreverence to carry off the feeling that she's a step ahead of everyone else. Underneath the bones of a delightful plot is a character who cares deeply but is very aware of her limitations, and therefore has taught herself to laugh at and be ruthless with her own emotions. I am finding it an incredibly compelling type of competence porn. I enjoyed the first book of this series, but this one was so much better. These stories are exactly the right length to keep the reader engrossed throughout and satisfied but wanting more at the end. How to Steal a Galaxy ends on a cliffhanger of sorts, to be resolved in the next and final book. I can hardly wait to start it. Highly recommended. Followed by Last Chance to Save the World. Rating: 9 out of 10

10 July 2026

Tim Retout: Blocking distracting news links

You are what you eat but perhaps this is even more true of our information diet. It is hard to strike a balance between remaining a well-informed citizen versus spending hours ingesting unnecessary news about issues and events we can t affect. But I m increasingly convinced that my hours lost to doomscrolling are down to design choices by web publishers rather than a failure of individual willpower.

We have created an obesogenic information environment I don t think it is just me I think our information environment has been progressively altered over time as news sites look to maximize engagement. Even outside of social media, the invisible hand of the market for eyeballs forces sites to optimize for browse time or risk irrelevance. Even as newspapers find it increasingly difficult to fund good journalism through advertising in an online world, especially local journalism, they need to keep readers on their sites, clicking through as many articles as possible. Clickbait headlines, urgent flashing live icons to draw the attention, and many opportunities to leap from one article to another, and another. But this design approach even extends to news organisations with a different funding model, like BBC News, which is a public service (state-owned but arms-length) organisation funded through a mandatory television licence a matter of controversy in some quarters. And it extends even to sites where I pay a subscription fee; I might get adverts removed, but I am still bombarded with the same design philosophy; too many opportunities to be pulled away from what I m reading towards some other unrelated article. Even if I try and limit my exposure to algorithmic discovery of new news, via RSS feeds or similar, if I m reading the full article in a browser then I am prompted to read more stuff that I didn t intend. This defeats the benefit of curating a set of feeds, because you still get dragged away to random articles.

Only 44% of BBC News is news To show you what I mean, I m going to pick on the BBC, although I love them dearly and the same issue very much applies elsewhere. I ve taken a screenshot of a random BBC News article in mobile view (my preferred doomscrolling user access device), and measured approximately what proportion of the full length of the page is taken up by each section. This is a fairly in-depth news article, so I reckon if anything the figures would be worse than this on shorter articles. A full-length screenshot of a BBC News article showing proportions of the page allocated to the main article vs. related links etc. (These numbers will not sum to 100% for reasons which are obvious if you look at the crossbars. Also they re approximations.) Less than half of the page (44% if you exclude the inline related links) is actual news text/images; the rest are links trying to help you find the next thing to read/watch. I do not want this. I m sure this A/B tests well in terms of reader figures, but it sometimes leaves me exhausted it must take subconscious mental energy to ignore, or I spend too much time trying to keep on top of things. And remember, this is a publicly-funded site that does not rely on advertising!

Blocking out the noise If you are technically-minded, you can use an ad-blocker such as uBlock Origin to take back some control. Applying the following lines as a custom filter (Settings > My filters) brutally cuts out almost all of these links:
bbc.co.uk##aside
bbc.co.uk##footer>div:has(h2)
bbc.co.uk##[data-block="uploaderEmbed"]
bbc.co.uk##[data-block="links"]
Caveat emptor: I have not road-tested this for more than half an hour, so who knows what consequences this could have on your web browsing. In particular, international readers outside the UK will likely be redirected to bbc.com, the commercial arm of the BBC, where these rules will need adapting. Is it unethical to use an ad-blocker to remove these links? I would argue not. I am not depriving the BBC of any revenue, because I pay my licence fee. I might reduce the amount of time I spend on their website, but if anything the subjectively better experience might encourage me to consume more news from them, not less. In other circumstances (outside the UK for instance, where the BBC relies on advertising), the balance might be different.

Product managers, please find better metrics I lament the state of the internet in 2026. I now can t unsee these innocuous related stories links as a mechanism to grab my attention, and it s gone too far. If you are a normal person just browsing the news and looking to discover the latest important stories relatively quickly, I can see that these types of links might actually be useful for discovery; but I m actually reasonably sure that I m not going to miss out on anything major. You still have the option of the news home page if you want to be presented with more news for example, and it feels natural to go back to there when you ve run out of stories to consume. But it shouldn t be down to individual responsibility to ignore or geekily block these types of link; news sites with alternative funding models should find better metrics for engagement than hours spent on site how about optimizing for customer mental wellbeing, or minimizing time required to catch up with the news? There s no need to maximize clicks and eyeballs. This is a societal level issue, because we are all going mad with news over-engagement. Product managers, over to you.

6 July 2026

Aigars Mahinovs: How to make a good group photo

Taking a good group photo consists of multiple aspects: I can say with confidence that nearly everything here comes from having failed to do these things right at least once, even on the latest attempts, so this is an ideal to reach towards, not something we expect to hit every time. The Goal The main goal of a big event group photo is capture both the moment itself and each individual person inside that moment. We want people, who were not there to see all the people involved and get an impression of what it was like being there. It needs to show the breadth and depth of people that make up this group, this project. And we want people who were there to be able to look back the next week, the next year or in ten years and remember - ah, yes, I was there, I was standing right there with this grin on my face next to this wonderful person and I was feeling great. Hardware Based on the goal we want to have high level photographic gear that is able to capture both a broad enough picture to encompass all the people and some of their surroundings to communicate the context (without undue distortions) and to deliver enough detail and resolution so that faces and facial expressions and underlying feelings of every single person in that group could be clearly seen and preserved. To both capture the context and minimise distortion the final picture should be just a bit wider than normal human field of view. That is about 50mm for a full-frame camera or 35mm for a typical 1.6 crop camera. You can go a bit wider if there are no better alternatives (as detailed in the scouting section), but be prepared that corners of the image will be distorted and not really usable (but we can fix that in processing step). Or you can go to unusual aspect ratios, like we did in Debconf 10. In the absence of a 100MP+ camera, you will need to be stitching together multiple frames to achieve resolution high enough to have enough pixels-per-face to see emotions clearly. This means that the photos you will actually be taking will be tighter than the overall field of view mentioned above. Still, a higher resolution camera body is preferable - nowadays 24MP-32MP cameras APS-C provide a good compromise between resolution and price, but 45-67MP full-frame cameras also exist on the market. Assume that we will be shooting in a bright environment, so most likely with quite low ISO settings, that means that high-ISO noise characteristics of more expensive cameras will not really play a role here. You will also not need very fast burst modes, even manual speed of one frame per second is sufficient. You will also want to get as much detail as possible out of your lens, and this is the most important part. You can do amazing work in all other steps of the process and have a great camera too, but if you pair it with a lens that is not sharp, then the end result will be disappointing. You want the lens that is sharpest corner-to-corner when stepped down to about f/8-f/11, that you can get for your system. You also want that lens to be about 85mm full-size sensor or 50mm for 1.6 crop size. Luckily that kind of range is also a great range for optical design and sharpest lenses are typically available in exactly these kinds of sizes. You absolutely want to have a fixed focal length lens, not a zoom lens. Even profession grade zoom lenses often deliver worse image quality compared to fixed lenses that cost less 1/10th of their price (when shooting in the same focal length). Newer design lenses are better than older lenses - optical design, coatings and precision manufacturing have advanced a lot over the decades. Retro look is great for mood, but not as good for actual resolution and clarity. You don't need to overpay for most expensive lenses because those often only improve image quality on lower F-stops. To encompass the whole group we will need to shoot at f/8 and in bright light, so the extra benefits of those f/1.2-capable super expensive lenses will not come into play here. We will have no use for a flash here. A tripod will be too restrictive when rapidly repositioning the camera between different parts of the panorama shoot. But a monopod might help with stability - I have not tried that myself, however. For my last photos I used a Canon EOS R7 (32.5MP) with Canon RF 50mm f/1.8 STM lens and considering an upgrade to Sigma 56mm f/1.4 DC DN for the next time. Scouting Scouting a good location for the group photo is another big chunk of a successful picture. The critical piece of the puzzle is lens-to-face distance. In order to keep everyone's face in-focus and have enough resolution on the farthest faces (without making nearest faces truly massive) we want to do everything possible to reduce the variance in lens-to-face distance - to reduce the difference in distance between closest and farthest face. The most effective way to do that is to have the photographer climb higher. To see this in action on the Debconf photos, compare Debconf6 (very high camera position, group on level ground - good) to Debconf10 (camera not too high, group on stairs, still good) and to Debconf17 (camera could not get high enough and the group is on flat ground - not great). Even the Debconf25 photo was suboptimal from this perspective. The Debconf23 photo was a very good example from the recent years - good height and also the group was positioned in a semi-circle so there were no people directly in front and very near to the camera. So you are looking for the highest point you could get to (even if that requires a special permission of key or a ladder) with a field large enough to fit the whole group comfortably. How to check that? Normally I simply take a photo from the top of the whole area and note down from there where the extreme corners of the group could be and still be fully seen in the shot - not blocked by trees, buildings and shadows. Then I go down and measure that space. Rule of thumb being - people in one horizontal line can stand 1 normal length step from each other and two horizontal lines can be half a step from each other vertically. So I can just measure a rough rectangle in steps, multiply the sides, multiply that by two and I have the rough number of people that can fit there for the photo. Once you have a candidate location or two, it is important to check them at the same time-of-day as you plan to do the photo (see organization section for that). You want to make sure that the whole area of the group is in the same illumination - if half of the group is in the sun and half in a shadow, then you will be having a very bad time later. The absolute ideal positioning for the group photo is to have everyone be in shadow, but still have enough bright skies and bright buildings in front of the people to give good illumination of the faces. Worst you can do is have the sun be behind the people (so all the faces are really dark) and second worst is have the sun be directly in front of the group, so that the faces are very well illuminated, but everyone's eyes are closed because they are being blinded by the sun. And sometimes all you can do is pray for some light clouds to provide for even and dispersed light. Debconf23 was very lucky that way. Another consideration is to how people are going to get to that place. You need to consider accessibility needs of people (it is ok, if it takes more effort or time, but it needs to be organized and communicated well in advance). And you need to consider how the big masses of people will be getting there - how to tell people where exactly it is and how to get there from various locations where people might be hanging out during the event? Having an alternate location indoors might be necessary if the weather report for the next days is not sufficiently predictable. We had to use that contingency in Debconf9, for example. Organization It's hard to take a good group photo if half of the group does not show up or is too late, so this needs some organization to happen smoothly. First of all you need to choose date and time for the photo. The photo does not take too much time from the schedule of the event and can be squeezed in after all the other events are already scheduled. In fact I prefer that as it allows you the flexibility of choosing the date based on weather conditions and time based on light and shadow conditions in potential photo spots. You don't want to choose the daytrip day as most people will be away and return times are not really predictable. You do not want to choose the morning after Cheese and Wine party for obvious reasons. First day and last two days are also sub-optimal as some people arrive late and some leave early for various personal reasons. Also you don't want it to happen just before Cheese and Wine either because then you'd have very little time and clarity to do the processing of the image on the same day. For timing, the best way, in my experience, is to schedule the photo directly after the end of talk sessions before a meal break - lunch or dinner. Typically in the Debconf schedule there are 2-3 daily breaks planned, say for Debconf25 there was lunch, afternoon break and dinner. Talks are planned to end ~10 minutes before those breaks (and meals) begin, so for example, afternoon break starts at 16:00 and all talks in the previous block end at 15:50. In such a case just schedule the "Group photo" event from 15:50 to 16:05. This gives people the info to go there directly from the end of all talks and that they will have sufficient time for break/meal afterwards. Do not forget to specify the location (as exactly as possible) in that event entry and make sure to post it at least two days in advance. People often want to wear something specific for the photo and thus need to know about it in advance. This also makes sure that people do not make alternate food plans for that specific break and don't leave the venue. Announce the date, time and the exact location as wide as possible, don't be shy. Announce and discuss mailing lists, IRC, Signal, Telegram, make sure the front desk knows in case anyone asks in-person, ... Check that it is again included in the announcements email on the day preceding the photo date. When the date has arrived, it is a good idea to check in early with people with special mobility needs to make sure they know where to go, how to get there and how much time they will need to be able to get there on time. As the final round of talks before the group photo is starting up, it is time to recruit "runners". I've had great success with this technique. The idea is pretty simple - for each room where people congregate (talk rooms, hacklabs, cafeteria, outside hackspace, front-desk, ...) go there and choose one person. You want to choose a person that you will recognise and remember among everyone else in the group, either because of who they are or what they are wearing, whatever works best for you. If they agree to help, instruct them to: "at end of talk, announce that the group photo happening now and the location, herd people towards the photo location, be the last person out, make sure there are no stragglers from this area behind you, when you arrive to the photo place I will assume that everyone else from this room is also now there, when you are there catch my attention and show this sign so I know for sure that it is all good and make sure that I did see it from you". With that sorted out all you will need to remember is how many runners you recruited and how many have reported in to figure out if everyone has now arrived or if we still have to wait for someone or some group. Then you will only have one last point of organization left - shaping the crowd into a group. People will not know what your vision for the group photo is, so you will have to give clear and LOUD instructions on where people should not be standing. Use clear, large gestures to support your words. You want to compact the group, have the people that just joined in the last moment and are standing to the side come deeper in and join the crowd. Have any holes in the middle of the crowd filled in. Forming a semi-circle instead of a blob helps with averaging face-to-lens distances. Make sure people are not in unexpected shadows. Make sure carried objects, like umbrellas of flags do not cover the faces of other people. Take the time to look at everyone face to make sure there are no people hiding behind someone's shoulder - typically they are not aware that their face is in fact not really visible. If there are such people, call them out and point directly at them and encourage them to step forward, if they wish to do so. You are the only one seeing the final picture now and only you can correct it before capturing the moment. So a few extra seconds here are worth taking, even if 300+ people are standing in scorching heat and waiting on you. When you are happy with what you are seeing, make sure to tell people clearly that you are now about to take the pictures and again remind them not to move and explicitly not to turn their heads to the side until you are done (this is the source of most of the extra work in processing). Be very loud and clear and make sure you have everyone's undivided attention before you start saying the important stuff. When done - say so. There will be other groups that will want to also have a photo taken after the main group is a bit more dispersed, so don't run away. Typically at least the T-shirt group will want a picture and also all the organizers. Final bit of organization during the group photo shooting itself is the sneaky self-insert. You may choose not to bother with it, or do it in the simplest way, like I did in Debconf6, but if you really want to blend in with the crowd, you need to have someone else take a photo of you in the exact same location at the same date and time from the same location. So you should already during shaping the crowd decide where you would fit in, it is easiest to blend in at the back of the crowd and to one or other side, so that it appears like you are just standing behind the shoulders of a couple peoples. Remember that spot - it is easiest if you stand in the exact same ground spot when your photo is taken. Just go down, recruit a volunteer to take your photo, make sure the settings are fixed to the same ones as for the group photo shots and have them take a handful of shots of you - one of you centered in the camera frame and a couple more with you more towards the corners of the frame. This distortion from being off-center in the frame may be important later. Preparation In addition to preparing the crowd for the photo, you also need to prepare yourself and the equipment. Make sure you have dusted your camera sensor and cleaned both inside and outside glass of your lens. It is usually a good idea to remove any filters from the lens. Install the hood, if that could help with blocking the sun flares. Make sure you have the right lens and that you have installed the right lens. For fixed settings I typically shoot in JPEG with RAW being there more like an emergency backup. The extra dynamic range of RAW could be used, but it is really complex to do that in combination with image blending and it is hard to get right, so I prefer an all-JPEG workflow and fix the dynamic range in the scene itself, before shooting. For Canon I am using the Standard profile that boosts the color saturation and sharpness a bit as I just enjoy that look and find it hard to get anything significantly better from RAW data even with a lot of effort. In any case make sure you have enough space on the cards to take at least 100 images and that you have a full battery. Do not use high speed burst setting because it is then too easy to take too many pictures at the start of the sequence and be stuck with your camera still in "Busy" state writing big RAW files to slowish SD cards and not allowing you to finish the full picture rapidly. You want to have the shutter speed at at least 1/100th of a second to prevent blur from both your hand movements and also from people in the shot moving around a bit (image stabilisation will not help you there). And you want to have the aperture to be around f/8 - lower apertures risk people in front or behind falling out of focus, make the lenses look less sharp. Higher apertures also start to become less sharp due to diffraction effects above f/8. ISO should stay as low as possible, ideally at ISO 100, but if there is not enough light then upping the ISO to 400 would be the first step that I would try to do and second would be decreasing the aperture to f/5.6. If there is too much light, then increasing the shutter speed should be the safe thing to do. As people start to arrive into the shooting location - check the exposure and nail down the settings, ideally in manual mode. Consider that left side could be a bit lighter or darker than right side. Err on the side of making the picture a bit too dark as there is more depth to darkness before cut-off compared to clipping on the high end. However, do not trust the exposure detection, instead take a picture and look specifically at skin tones in faces of people that already are standing in the photo area. Faces are the key bit and the exposure needs to be adjusted just to the faces and ignore darker of lighter clothing. Do some test shots and find settings where faces look not too bright, but also not very dark and fix those settings in manual mode. Now you are ready for the action. Shape the crowd, check the faces and the action can start! Execution During taking of the group photo you want to finish it fast, but at the same time you have to take the time to make it right. If you hurry too much under pressure, you risk being left with unusably blurry images and the whole effort wasted. Having already prepared and verified the manual settings makes it easier. When you are taking pictures, you have to remain as still as possible - even at very high shutter speeds even slow hand movements are still bad for image quality. So think of the movement as of biathlon athlete shooting the very middle of five, very separate targets - take a burst, reframe, then steady up for a second and only then take the next burst. 3 frames per burst are sufficient. 90% of the time the very first photo of a burst will be best. As you move from frame to frame, aim for just a bit more than half-frame overlap. This will give the opportunity to skip frames if all is good, but also have backup coverage of every face in case of problems. Proceed systematically, I typically start off on the top left of the crowd, then go right until the end of the line, then shift down half a frame and go left until the end and repeat until I am done with the crowd. After that it is very helpful to also immediately take photos of a "frame" around the whole crowd. Stitching process often distorts the frames in weird ways that leave holes in the resulting image that you can fill if you have a wide frame around the crowd. It is possible to compensate with creative cutouts in the final image (like Debconf9), but the more framing room you make, the more flexible you will be able to be with cropping of the final photo. The frame also gives you the opportunity to capture more of the context of the place and space. As an example, Debconf25 group photo in the end consisted from 9 images + 1 for sick people + 1 for me. I ended up missing the framing shots for bottom left, top left and top right corners. To get there I took 68 images. And in some years it was more than a hundred. Processing This part might be less stressful than taking the pictures from intensity perspective, but it lasts longer. Depending on you luck, skill and perfectionism it can take anywhere from 3 to 9 hours of work to complete. Before you start, however, you should first request things that you will need for other people. This can even be done before taking the actual group photo, but usually I forget. To finish the photo you will need three things: The first two you should be able to get from the respective organizers. The motto is harder. I typically try to ask the current DPL to come up with something describing the current mood of the project or of the event, but it is rare that it is that easy. Most of the time I came up with something as I was editing the photo and reflecting on what was the mood, the feeling, the mojo of this conference and of this year was like. Bend that around a recognisable phrase or expression, make it a bit more insider-relevant and you are on the right path. Some years this was the hardest part. For the panorama stitching I will describe the workflow that has served me good for years, but maybe there are better ways possible nowadays. Feel free to let me know! First I would save all photos taken and select one sharpest photo from every burst. Next I would select the minimal number of photos that appear to be covering the entire crowd. The fewer images you use, the better in the end because the most quality problems crop up in the areas where photos are getting stitched together. Fewer seams leads to fewer issues. Open Hugin (you will also need enblend and enfuse installed) and import your minimal set of images into it. Click the "Align" button and wait a while - the processor will be trying to figure out keypoints in each image and then try to match these points between the images to try to fit them all together into a single projection. To do that it will distort the images. This is the trial and error process part. You may need to add, remove or replace images to get the stitching to work or to work better. You may want to add more of the frame images to fill the ragged holes around the image. After initial alignment, go to "Move/Drag" tab and move the image a bit up in the projected field of view and make it a bit more central visually. That will help a bit with the distortions in the near-by people and people in the corners of the image. In the "Crop" tab set the initial crop - leave it generous, you can always crop more in later steps. Do not be afraid of leaving in sizable chunks of black homes, empty skies or grass. All of that can be filled in later as well. Go back to the "Assistant" tab and click "Create panorama". It is good enough to have JPEG output at 100% quality using exposure corrected low dynamic range output option. Make sure to check the "Keep intermediate images" option. This will not only generate the final, merged panorama, but also keep around the individual images after perspective correction and exposure blending steps. These are critical for fixing blending error in the next step. You might need to go back a forth a few times with a different sets of source images, maybe adding some image between other two, maybe removing another to reach a better starting point. The key part to pay attention - how many ugly stitches are there in the image. Check every face, the blending algorithms do not recognise faces and sometimes try to stitch one face from two or more images creating very weird effects. They can be fixed in the next step, but it is rather hard manual work, so the fewer such faces are in the blended image, the less work you will have. In some years I've managed to find a combination where all faces were good and in other years I had to manually fix 13-15 faces. Do not try to blend the extra pictures (like with you or with sick people) into the main panorama with Hugin - it will get very confused with the parts of the grass that it is able to see where other people were standing. The next is the final processing in GIMP. Think of it like a large and complex project - do as much as possible in separate layers, save often. Fixing wrongly stitched faces and also putting yourself into the photo are very similar activities in the end. Just the scale and the source differ. For yourself you just cut out yourself (upper torso is enough) from the separate photo. For corrupted face, choose one of two intermediate images that the Hugin created where the face is transformed, but not yet merged (with a different version of itself). In either case crop the photo to roughly the interesting size and put roughly in the right spot as a separate layer on top of the group photo background. Reduce the opacity of the small layer to 30-40% and zoom in to 400%. With that it is much simpler to position the layer with pixel precision. Then all you need to do is add a layer mask to this layer and paint it just right. Basically in layer mask black means transparent and white means non-transparent. So you need to just make everything that is you have white mask and everything that is not you have black mask. And smudge the border a bit with finger tool or blur to make the transition smoother. Easy to say. Hard to do. This is what takes most of the actual work hours in post-processing. You might miss someone. I am sure Phill is just thrilled to see me in the very middle of the Debconf25 final picture .... But do try to fix them all. Use large, sweeping geometric figures to cover up black holes, empty grass fields and other sub-optimal corner features. And then use that newly created free space to put in a large version of the logo of this years conference, decently sized motto and slightly smaller invitation to the next years conference. Do not forget to add a copyright and license statement somewhere in the corner in smaller, but still well readable font. I am using a text like: "Photo by: Full Name, Email: fullemail@debian.org, License: GPLv2+ or CCv3-BY" This ensures that this image may be used in any press coverage (with basic attribution) and also can be included in any GPL-licensed software, if that ever comes up. The same statement is also in the metadata of the image file (see Image-Metadata-Edit metadata in GIMP) along with information that states that this is "Debian Developer Conference Group photo, City, Country, Year". Image->Image properties->Comment is another place where GIMP hides this EXIF information. For ease of use, in addition to a full-resolution image it is also useful to make a lower resolution version that would still fit on a 4K screen at full resolution, so about 3840px wide. Some photo hosting services set other limits for image size as well, so it might be needed to scale the image down below 100Mpix to upload it to Google Photos, for example. Publishing So, it is finally 1AM and the group photo is ready! How do you push it out to people? Well, in all possible ways and places. Again - don't be shy, people do really want to see it. Push it to whatever you use for your shared photos. Push it to Debconf shared git (note that this is GIT-LFS repo, make sure you know how to add content to the LFS specifically). All permanent links to that in GroupPhotosAll wiki. And then send those links to IRC, Signal, Telegram groups, debconf-announce mailing list. Publish it in your blog and push that to Debian Planet. Push it in Threads, Bluesky and Mastodon. Send an email separately to Debconf orga team. And one to Debian Publicity Team so they can put it into the Debian Home Page and push via Debian micronews accounts. And that is about it. Now you can go back to enjoying the rest of the conference. Or running around doing other things that you think need to be done. It's up to you. You did it. This moment will remain with people for a very long time. And you helped. Questions? Feedback? Just ask here or here.

27 June 2026

Russ Allbery: Review: The Folded Sky

Review: The Folded Sky, by Elizabeth Bear
Series: White Space #3
Publisher: Saga Press
Copyright: June 2025
ISBN: 1-6680-7812-0
Format: Kindle
Pages: 483
The Folded Sky is a far-future space opera and a fairly direct sequel to Ancestral Night, but with a different protagonist. You do not need to have a vivid memory of the previous book to read this one. It is somewhere around Elizabeth Bear's 31st (!) novel, depending on how one counts and what one includes. Sunyata Song is an archinformist, which is sort of an archaeologist, sort of a librarian, and sort of a historian. She recovers, decodes, and organizes information so that it can be preserved and made usefully available. As the book opens, she is, after an exceedingly long white space journey in an actively hostile ship with a (to Sunya at least) an atavistically off-putting crew, reaching her goal: a vast artifact that I won't describe further to avoid any spoilers for Ancestral Night. She is eager to get to work, an eagerness that is both heightened and made more anxious by the discovery that her academic rival and abusive ex has arrived before her. The pirate attack doesn't help, nor (at least at first) does the surprise appearance of her wife and kids. The opening of this book is a lot of infodumping mixed with nearly stream-of-consciousness emotional dumping. The style shift in this series continues to surprise me; previously, Elizabeth Bear books avoided reader hand-holding to the point of bafflement if you weren't paying close attention. Not here. The Folded Sky takes the shift perhaps too far, and I almost stalled out at the start of this book when Sunya's near-constant self-conscious litany and analysis of fears and concerns started feeling like whining. The book picks up considerably after the attempted murder. About a third of the way through, The Folded Sky feels like it's settling into a recognizable subgenre of murder mystery except set in the far future with fascinating technology and aliens. There has been an attempted murder on a closed station besieged by pirates. There is a law enforcement officer present, but they don't have a lot of investigative experience. For various reasons, Sunya decides to start poking around while being conscious she has no idea what she's doing. The bumbling detective is a common trope, so I thought that was where the story was headed. It is, sort of. There is a mystery and Sunya is involved in solving it. But that's only a small fraction of what's going on, and by the end of the book the plot has shifted firmly back to the genre of space opera, with a side note of family... drama is the wrong word. Whatever one would call a story about raising a rebellious teenager while trying very hard to not turn conflicts into actual drama. I am fascinated by the characterization of this book. Sunya is something of an emotional mess, but Bear doesn't use that fact in the ways that I would normally expect. Similar to Ancestral Night, I finished this book thinking that The Folded Sky is primarily an examination of rightminding, but a more subtle one than the previous novel. Rightminding is a central technology of the White Space series, and I suspect its intended thematic core. Humans in this civilization are equipped with near-universal implants that allow conscious manipulation of one's neurotransmitters and thus emotional state, either by the wearer or by a helpful nearby AI. The fox, the implant used to accomplish this, comes with some other features such as sensory recordings and the ability to load ayatanas (James White style personality recordings to provide some bit of necessary expertise), but rightminding is its primary and most frequently-used function. It is the critical technology that allowed humans to break out of cycles of endless war and join the other peaceful inhabitants of the galaxy in a shared civilization. The name is (intentionally, I assume) Orwellian because Bear knows that many readers, particularly those from the US who have been steeped in simplistic libertarian ideas, will find the idea profoundly creepy. (This was a major plot point in Grail.) This book is not the argument for the technology, though; Bear dealt with that in Ancestral Night. This book is a look at its practical messiness for a person who needs a lot of psychological support. Sunya is anxious, prone to catastrophizing, hates surprises, has some PTSD-style symptoms around space habitats due to earlier trauma, and is also dealing with the unwelcome reappearance of her ex-girlfriend who stole her work. Her first-person narration tends towards insecurity and anxiety spirals, and in another book this might signal an unreliable narrator. In this book, though, there are no dramatic emotional revelations or backstory twists the way there were in Ancestral Night, and the resolution of her troubled relationship with her daughter only partly hinges on plot developments. Instead, Sunya muddles through, with a lot of self-analysis, help from her fox, and a great deal of support from her wife. This makes it sounds like the emotional mess at the start of the book is left unresolved at the end, but that's not true at all. The muddling through works! Sunya keeps doing things that I thought were foreshadowing some catastrophe, but she knows herself better than the reader does. Bear largely avoids the sudden ruptures that are normally used to resolve emotional problems in fiction. Instead, Sunya spends a lot of time and energy working on her thinking and her relationships while trying to be ethical and useful, and those efforts slowly bear fruit. I'm worried this makes the book sound boring; rest assured that it isn't. This emotional subplot is only an undercurrent in the novel, and the main plot has enough weird science, alien aliens, and space opera drama to satisfy my page-turning desires. I'm focusing on the emotional arc in this review because I find it so unusual and so oddly compelling, particularly in retrospect. This is not how one normally does emotional development in a novel. Sunya's fox and rightminding aren't even the focus except when the pirates express their typical libertarian disgust for the idea. Rightminding is an entirely normal part of Sunya's life that she relies on. It doesn't solve all of her problems, but it gives her a foundation from which to tackle them in the slow and frustrating and inconsistent way that is required outside of novels, via a long series of small decisions to be the person she wants to be. I think The Folded Sky will be more hit and miss for readers than the other books of this series. Sunya was, for me at least, a much harder character to like early in the book, and it takes quite a while for the plot to get going. But this is one of those books that I've not stopped thinking about since I finished it. I think it makes a fascinating pair with Ancestral Night. The first book makes the philosophical argument for rightminding, and this book shows the practical reality with all of its messiness. The Synarche has some significant flaws (including the status of AIs, which is another interesting subplot), but it's a workable system. It feels rare to read a science fiction novel that shows this level of messiness without pairing it with an argument for radical change, and as frustrating as it was to read in places, I am intrigued by the overall effect. Sometimes acknowledging problems and working on them within an existing framework works. Followed by a book tentatively titled Shipwreck Star that does not yet have a release date. Rating: 7 out of 10

20 June 2026

Gunnar Wolf: systemd for Linux SysAdmins

This post is a review for Computing Reviews for systemd for Linux SysAdmins , a book published in Apress
systemd. Yes, in full lowercase. If there was ever a technology to cause controversy in the Linux world, this is it. Since its inception in 2010, systemd s goals were set quite high: to replace the vital part in every Linux system that takes care of the system boot process. It quickly reached maturity, allowing it to be adopted as the main init system in most major distributions just five years later. Despite describing events that happened over a decade ago, systemd adoption still raises the temperature in any Linux-related discussion. David Both s comprehensive book tackles the what, why, and how issues surrounding systemd. Carefully divided into 16 chapters, going from the basics and some of the technical and political history behind the project to the different subsystems and aspects covered by systemd, its almost 450 pages can scare people away. But the text is written in a very clear, tutorial-like fashion, and while it can be read sequentially, cover-to-cover, readers can also pick a single aspect and jump straight to the relevant chapter. A frequent criticism of the systemd project is that it aims to basically rewrite all of a Linux system, and just looking at this book s index shows there is some truth to it. The first chapter is an introduction to the systemd project and a brief overview of its history (including the controversies around it), and the following four chapters deal with understanding and controlling the system boot process. That leaves ten chapters to cover different aspects or subprojects of systemd, such as time and date issues (synchronization, time specifications, and controlling repetitive tasks), understanding and leveraging the system journal that strongly departs from the old syslog system, network configuration and firewall management, system health and performance debugging all aspects that in the traditional Unix philosophy were managed by independent programs. And I can identify several systemd subprojects not covered by this book! We long-time Unix and Linux administrators took pride in how highly performant and stable systems were supported by the simplicity of our tools; systemd critics point out this massive project has absorbed dozens of individual tools, yielding corporate control over vast swaths of vital system tooling. Truth is, as a sysadmin myself, systemd is today one of my greatest allies. I appreciate how the author evaluates every component independently, including his personal evaluation of each even acknowledging when he prefers working with the traditional programs. If I had to note one criticism: given the many console captures, having a maximum width below 70 characters means several lines are unnaturally cut short (and continued with odd indentations). There is probably no right way to solve this, but it does affect the reading experience.

23 May 2026

Amin Bandali: Thinking about life - chat with Protesilaos

In the recent weeks I've been engaging Prot as a coach to help review my new ffs package for GNU Emacs as I worked on preparing it for inclusion in GNU ELPA, as well as discussing other Emacs- and life-related topics. UPDATE 2026-05-23 22:39:15 -0400: Prot also published an article about our session on his website: https://protesilaos.com/commentary/2026-05-23-life-issues-and-philosophy-amin-bandali/ In our nearly 2-hour conversation, we discussed at length and in depth various aspects of life in the current times. For instance, feeling overwhelmed in the face of innumerable things happening at once, with technology changing our perception and making events feel proximate and imminent. We talked about seasonality and rhythms in life, including in relation to burnout and knowing our own limitations, and descriptive vs prescriptive thinking when reflecting on the expectations we may place on our self when comparing our self to others through the lens of our necessarily-incomplete impressions and glimpses of their lives. We discussed absence or loss as a dual to presence or persistence in the process of life. How with our memories and through embodying the philosophy and teachings of departed loved ones their essence and legacy continues to live on within us. But also loss in the sense of us losing parts of our self in life-defining moments while preserving other parts and gaining new ones, being liberated of some of the burdens of our past self and in effect becoming someone else in the process. In being true to our self, we talked about humans as multi-faceted beings and the importance of expressing and giving a voice to these different aspects of our self, and keeping alive that child-like sense of awe and wonder. To live a life where the pace and rhythms of our environment are in sync with our internal rhythms, and to not give others undue power over us or our happiness through trying to live according to their prescribed standards or expectations. I also learned more about Prot's practical philosophy of situational awareness in life, not merely as a means for survival, but also as a way of appreciating all of the beauty that surrounds us, and a method for gaining the knowledge and skills to apply what we learn from patterns in one area of life to other areas. We concluded our session with a mention to the concept of sanctity, to set aside a sacred time or place for our self wherein no distractions are allowed, where we can unwind, rest, and recharge for whatever comes next. Here is the video recording of our session, which I share with Prot's permission: You can view or download the full-resolution video from the Internet Archive. Like Prot, I am invigorated and inspired to live a full, honest life. To do my best, do what I do in earnest, and make the best of what I have. Take care, and so long for now.

17 May 2026

Otto Kek l inen: Balancing persistence vs pivoting is grit a virtue or wasteful?

Featured image of post Balancing persistence vs pivoting   is grit a virtue or wasteful?Being persistent, sticking to a plan and showing up to work every day is generally valued highly across all cultures as virtuous behavior. It is obvious that anything of value and worth achieving is also not easy, but requires significant and recurring effort. Learning a new language, winning a sports competition or building a successful business are all typical scenarios where grit plays a central role above everything else. However, sometimes the virtue of tenacity can result in just a waste of energy. The question is then: how does one recognize that true progress is being blocked by stubbornness and a pivot would be the correct decision, as opposed to being close to breakthrough where doing more of the same would actually be the right choice?

What is persistence actually? To think clearly about this topic, one must first grasp the concept of grit and what it looks like in practice. Research by psychologist Angela Duckworth on grit shows that sustained effort in the face of setbacks separates high achievers from those who quit too soon. Entrepreneurs who iterated through dozens of failed prototypes or writers who revised manuscripts for years understand this truth. Persistence builds resilience, deep expertise, and the kind of compounding results that shortcuts cannot deliver. It also protects against the distraction of shiny new ideas that pull focus from what actually works. Persistence is about:
  1. Believing in an outcome and working towards it despite people around you not sharing the belief, and despite your own work and experiments not being successful.
  2. Continuing to hold the belief and sticking to the decision despite other ideas, solutions and competing alternatives surfacing.
  3. The more time passes, the firmer the conviction becomes. Time, money, and emotional energy invested in a failing direction create psychological pressure to continue (sunk-cost fallacy).
Simply following through on a plan or upholding a contract is not true persistence. Grit is a personal trait one can cultivate to actually become more energized to do something precisely because it turns out to be harder than expected.

Pivoting: a calculated choice The opposite of being persistent is giving up. Pivoting is not about giving up, but about redirecting the energy and momentum towards a new goal. Pivoting requires coming to the realization that you were wrong, and going through the painful process of discovering a new truth. Ideas tend to be abundant, and doing something new isn t hard as such. The hard part is to abandon a previously held belief and adopt a new one with equal conviction. To have that conviction you need to have data and metrics. This is also the key to how to decide between persisting vs pivoting at any moment in time.

Key metrics of success Any decision is only as good as the information available at the time it was made. To be set up for success one needs to start by deciding on what the actual goal is, what one values and how progress is measured. Key metrics are usually easiest to discover by working backwards from the goal. If you want to build an electric car, you might decide that the goal is to have a car that costs 30,000 euros and can drive 300 km on one charge. From that goal you can break down what the cost structure should be, what volume of production is needed to break even, what raw materials are needed and what the battery chemistry needs to achieve to meet the goal. That can further be broken down into a rate of progress. Suppose the plan requires battery energy density to reach 150 Wh/kg to be viable. If the state of the art starts at 100 Wh/kg and funding lasts a maximum of five years, the team needs at least an 8% improvement every year (1.08^5 100 Wh/kg 150 Wh/kg). This can then be used as a guideline. Sometimes progress is not steady, but happens in jumps. Even in those cases there should be a trajectory to benchmark the jumps against. In an online business, the key metric could, for example, be one of these:
  • 7- or 30-day retention rate: Do new users who try the service actually like it?
  • Weekly or monthly active users: Is usage trending up?
  • Feature adoption rate: In an existing service, how many users are using the new feature?
  • Product-Market Fit Score (from Sean Ellis test): Percentage of users who say they would be very disappointed if the product disappeared. Above 40% is a strong early indicator. A number below that (after multiple iterations) is a good data point to pivot.
  • Revenue run rate or burn rate: The most generic metric everything eventually boils down to. Healthy markets reward good products.
Weekly metrics are better than monthly, as they make the feedback loop faster and allow you to get validation quickly and do minor course corrections along the way. A complete pivot should, however, be based on long-term data, driven by the key metric and supported by additional data points. Metrics are also needed because they can t be bribed or convinced to be anything other than what they are. Listening to other people is good, but just relying on the opinion of others is extremely dangerous because people are biased either for you or against you depending on whether they see you as a trusted leader or an outcast. Key metrics are of course domain-specific and everyone needs to come up with their own. However, you must have some key metric. You can t have the excuse that what you are doing can t be measured. If you are part of a larger organization and you need to advocate for a difficult decision for example, to kill your darlings when facing a pivot you need to have the metrics to back up your views, and those metrics need to have been established way before as something the organization values, and not cherry-picked just for this one decision. It does not matter if you are on a personal improvement journey, running a political campaign, inventing a new product, or growing a business you need to have some metric you can check at any given time to see if things are improving fast enough to predict success. Metrics can and should also be used in daily work to validate that you are on the correct path, and to optimize execution.

Famous examples of persistence and pivoting that led to breakthroughs In all of the cases below it is of course in hindsight easy to say they made the right decision. However, take a minute to try to imagine yourself in their shoes at the time of the decision. What metrics might they have had available to support their decision? What would you have wanted to measure or find out if you were in the same situation?
  • Frustrated that his vacuum lost suction, James Dyson spent five years and built thousands of failed prototypes in a backyard shed. He remortgaged his home, lived on savings, and faced rejection from every major manufacturer who wanted to protect their bag-replacement business. The 5,127th prototype based on an idea from a sawmill with a cyclone finally worked. Launched in 1993, the Dyson DC01 became Britain s best-selling vacuum within two years.
  • As a single mother on welfare in the mid-1990s, J.K. Rowling finished her manuscript for Harry Potter and the Philosopher s Stone while battling depression and poverty. She hand-typed copies and mailed them to publishers. Twelve rejected it outright, with comments like children s books about magic don t sell. She nearly quit multiple times but kept revising and submitting. Bloomsbury finally accepted it after the CEO s eight-year-old daughter read the first chapter and demanded the rest. The series has since sold hundreds of millions of copies worldwide.
  • Founded in 1997 as a mail-order DVD rental service, Netflix added unlimited subscriptions in 1999 to compete with Blockbuster. By 2007, broadband growth and declining DVD sales signaled a shift. CEO Reed Hastings pivoted aggressively toward streaming, investing in bandwidth deals and original content while de-emphasizing physical media. The move faced skepticism, but eventually changed the whole culture of how entertainment is consumed.
  • YouTube launched in 2005 as a video-dating site. Founders offered money to women who uploaded dating videos, but almost no one did. Meanwhile, users uploaded random clips. The team recognized the mismatch and pivoted within months to a general-purpose video-sharing platform with easy uploading. Google bought it just 18 months later.
  • Instagram began in 2010 as Burbn, a location-based check-in app that let users post plans, earn points, and share photos. Co-founders Kevin Systrom and Mike Krieger quickly noticed users ignored most features and mainly used it for photo-sharing. They made the tough call: scrap everything else. Within weeks, they rebuilt the app around clean, simple photography with filters. The pivot launched as Instagram in October 2010. It gained 1 million users in two months and was acquired by Facebook just 18 months later.

Insanity or conviction? English has several proverbs that warn against excessive persistence, such as banging your head against the wall . Insanity is commonly defined as Doing the same thing over and over again and expecting different results. In Finland, the national identity is practically built on the concept of sisu . It means much more than just grit . The word is derived from the word for inside or guts and represents an unexplained, almost superhuman force that makes one stoically take action despite seemingly impossible odds and somehow succeed anyway. It became a defining national mythos during the Winter War (1939 1940), where a force 10 times larger than the Finnish army tried to invade the country but was stopped and Finland just barely managed to keep its independence. The word sisu transitioned from a character trait to a pillar of national survival. I think Finns survived because the more you believe in persistence, the more likely you are to persist. I view persistence as a religion that requires faith, while pivoting is a science where you derive the truth from the numbers. When in doubt, I would always choose persistence over pivoting. Perhaps it is because of my genetic tendency towards having sisu , but I would also rather keep on going a bit more and try one more time before giving up and pivoting in order to get more data, so that when I pivot, I know it is absolutely the right thing to do at that point. Depending on the situation, the costs of postponing the pivot vary. Of course, if the main metric is the burn rate and a company is running out of money, a pivot must be done early enough that the remaining runway is enough to execute the pivot, and then some more. In some situations a business idea might simply be ahead of its time. If that is the conviction and the key metrics support it, the best way to navigate the situation is to cut down on costs and wait for competitors to appear, help build general awareness, and then ramp up again to ride the wave. Remember that success does not come from grit alone there is always an element of timing and luck as well. But if you are not persistent and stop showing up every day, you won t be able to seize the opportunities if and when they arise.

Failure is the likely outcome you have to avoid it at any cost One must also realize that most attempts end in failure. Failure is the baseline, and success is the exception. To reach a breakthrough, one must be stubbornly persistent. In particular, if you are a leader, you need to be so high in conviction that it almost becomes an aura that radiates to those around you. Postponing the decision to pivot allows you to get a bit more data for the decision, so that once you pivot, you have full belief in the new direction. Once you pivot, there is no looking back, otherwise you will undermine morale and most certainly fail with the new thing as people will execute it with hesitation. Failure is statistically always the more likely outcome. Most things end in failure and we never hear about them. If someone on your team does not believe in what you are doing, it is very easy for them to prove that something is a failure by spreading negativity, putting in less effort (perhaps unconsciously due to lack of conviction) and thus actually contributing to a self-fulfilling failure. In most areas of life, ideas are cheap and the only thing that matters is execution. To be good at executing, you need to be good at making decisions. When drafting plans it is good to have alternatives and a lot of consideration. However, when execution starts, there is no room for doubt, otherwise the chances of success decrease. Therefore, the best way of balancing persistence vs pivoting is to
  1. plan well ahead,
  2. establish the key metrics,
  3. have thresholds established for what would trigger a pivot, and
  4. do everything you can to move the metrics in the direction you want them to go.
Finally, if you decide to pivot, you must do so only with very high conviction, as you can t undo a pivot, and you should not be doing multiple pivots in a row either. If you are fully convinced yourself about the pivot, you will also be able to convince others about it, and carry the momentum.

4 May 2026

Russ Allbery: Review: Full Speed to a Crash Landing

Review: Full Speed to a Crash Landing, by Beth Revis
Series: Chaotic Orbits #1
Publisher: DAW
Copyright: August 2024
ISBN: 0-7564-1947-6
Format: Kindle
Pages: 153
Full Speed to a Crash Landing is a science fiction novella and the first of a series. Beth Revis made the New York Times bestseller list for an earlier series of young adult science fiction novels, but somehow I had not heard of her before this series. Ada Lamarr is a salvager. She picks up material from crashed or dead ships for resale. As the story opens, she has a large hole in the side of her ship, she's running out of oxygen, and the other ship nearby is refusing to answer her distress call. By the time they finally respond, there is barely enough time to get aboard before she is entirely out of air. Ada's first-person narration drops hints that she may not be entirely what she seems. But then, neither is the Halifax, so it's only fair. The captain of the Halifax treats Ada with a great deal of suspicion and wants her out of the way of their ongoing salvage operation. However, the captain does not appear to be entirely in charge. Ada is immediately struck by the mysterious Rian White, who seems to have some authority over their mission and is more thoughtful and calculating than the rest of the crew. He's also handsome, which doesn't hurt. I was tempted to keep writing about the plot, but given the short length of this book, I should stop there and let you enjoy the twists and turns for yourself. This is a fun science fiction action romp: lots of banter, lots of tense moments, and a cagey first-person protagonist with an irrepressible sense of humor and a knack for brazening her way through conversations. It's not long on world-building (there isn't enough room), but Revis works in enough details to be intriguing and to set up some interesting motivations. This is the sort of book that lives and dies by how much you like the protagonist, something that you will easily figure out by the end of an ebook sample if you're the sort of reader who uses those. Ada is irreverent, talkative, and very adroit at diverting attention (entertainingly) onto anything other than the critical piece of information other people are missing. If you want to, I suspect you could easily figure out most of what Ada is up to before the book reveals it explicitly. It's not that complicated, and the book isn't really trying to hide, although it doesn't give you all the necessary information in advance. Personally, I was happy to sit back and enjoy the ride. There is no romance in this book beyond frequent comments from Ada that she would have liked there to be a romance in this book under different circumstances, but I will be surprised if that romance doesn't show up later in the series. Ada and Rian are clearly being set up as a pair. I didn't like Rian as much, mostly because he's less memorable as a character, but he comes into his own in the appendices after the plot proper. I thought those concluding appendices were the best part of the novella and question the Kindle formatting decision to treat them like supplemental material. They purport to be a series of government memos, fill in a lot more of the backstory and world building, and have the best footnotes. Don't skip them! This isn't the sort of book that I am inspired to immediately push into everyone's hands, but it's a fast, well-paced story that delivered a few reading sessions of entertainment. I'm not sure the political philosophy in the background makes a lot of sense, but at least not a standard stereotype of current politics seen in so much science fiction. It's going to set up some interesting character conflict in later books. I'm certainly intrigued enough to keep reading. Recommended when you're in the mood for some fast-paced fun that's short and undemanding. Followed by How to Steal a Galaxy. Rating: 7 out of 10

27 April 2026

Gunnar Wolf: Heads we win, tails you lose AI detectors in education

This post is an unpublished review for Heads we win, tails you lose AI detectors in education
Educators throughout the world are tasked with the difficult requirement of evaluating students works, making sure the grades meaningfully reflect the students understanding of the subject, and that a graded assignment maps to the relevant work invested in solving it. After the irruption of Large-Language Models in late 2023, this task became obviously much harder: if a widely available computer program is able to solve an assignment in a way that resembles a human-generated response, how can educators meaningfully grade their groups? As it has been the case with different innovations over time (such as with the appearance of electronic calculators or the mass availability of digital encyclopedias), the first reactions were of prohibition and denial: students who use the new tool in question are to be disqualified or somehow punished. It is only some time after the innovation in question settles that teachers find a way to properly weigh, integrate and accept its use. The authors of this position article present several arguments as to why it is impossible, unethical and unadvisable to use automated AI detection systems to process student assignments. The first argument is whether it is at all possible to reliably differentiate human-written essays from LLM-generated artifacts. The first criticism is that AI detectors are, themselves, LLMs trained on human-generated texts (negative) and LLM-generated texts (positive). However, the only way to assert the training material is not noisy is to use pre-2020 text as human-generated but natural ways of writing are influenced by what people read, and the authors quote studies pointing out that human language, particularly in the scholarly fields, has incorporated terms and constructions that were used as LLM markers. Quoting the authors, As exposure to AI-generated material becomes increasingly widespread, it is reasonable to expect that the linguistic patterns of human writing will shift, reflecting the influence of AI-assisted texts encountered across education, media, and everyday communication . Stylistic elements and other such markers are being adopted back into regular speech at a high rate. Then, the aspect of ethics comes into play as well. While it is expected that teachers should demand intellectual integrity from students, and plagiarism detectors have been widely accepted into the workflow of academics, the accusation of presenting LLM output as own work is necessarily an uphill battle: the accused party is tasked with providing proof of innocence based on nebulous, probabilistic accusations. The authors argue, once an accusation of turning in a LLM-generated text is made on a student, the onus on proving innocence lies with the accused. The authors review and argue against a series of techniques that have been presented in literature to aid teachers in detecting LLM abuse, such as linguistic markers, single or multiple AI detectors, the use of false references, hidden adversarial prompts, arguing in all cases the techniques fail to be trustable enough and highlighting the probability of both false positives and negatives. They also present AI detection as a false dichotomy: many works presented are not 100% human generated nor 100% LLM-generated, but some pertinent LLM-generated paragraphs are presented mixed with human-generated content, in a positive, critical AI use ( Students work is frequently created with, not by, generative AI ). The article closes by reiterating the authors position: AI detection in education is not merely flawed; it is conceptually unsound . they call upon institutions to accept the use of generative LLMs cannot be solved through surveillance and punishment , but has to be tackled by an assessment design that recognizes AI s role in learning . This article s position is very strong and well argued, and although it will surely meet with ample opposition, it surely poses an important, very current problematic. As a teacher, I found it a very enlightening read.

Russ Allbery: Review: What We Are Seeking

Review: What We Are Seeking, by Cameron Reed
Publisher: Tor
Copyright: 2026
ISBN: 1-250-36474-4
Format: Kindle
Pages: 339
What We Are Seeking is a bit hard to classify beyond science fiction. I think I would call it anthropological science fiction, but it's also a first contact story and a planetary colony story. It is a standalone novel (well, so far as I know; see later in the review for caveats). This is Cameron Reed's second novel after the excellent and memorable cyberpunk novel The Fortunate Fall, first published in 1996 under Reed's former name of Raphael Carter. John Maraintha is a doctor from the world of Essius. He took what he thought was a temporary job on the Free Ship Edgar's Folly, where he's endured considerable culture shock. As the novel opens, John learns that the colonists on Scythia have requested a translator to talk to one of the native life forms, and a doctor since they're down to only one. John will be that doctor. The captain has decided, and by the rules of the free ships, John does not get a choice in the matter. The Scythian colony is about four hundred people, now located in a desert climate since the complex native life forms destroyed their previous settlement. The colonists are a split between Ischnurans and Zandaheans, two other human civilizations from the scatter of colony worlds left after Earth embraced AIs (aiyis here) and turned inward. Both of those groups marry, something John considers a moral abomination. Neither of them seem likely to understand Essian sexual ethics. More devastatingly, John had intended to spend some time as a ship doctor and then return home to a new place in Essian society. Once he lands on Scythia, the chances of that are gone; it is highly unlikely any ship would pick him up again and take him home. I have been trying to find the right books to compare What We Are Seeking with ever since I read it. The best I've come up with are Ursula K. Le Guin (particularly The Dispossessed), Eleanor Arnason's A Woman of the Iron People, and Becky Chambers's To Be Taught, If Fortunate. The start of the book felt like an intentional revisiting of an earlier era of science fiction, with somewhat updated science and politics, but the last half of the book, where the action picks up considerably, is a meditation on gender, social systems, religion, and small-group politics. All of that is mixed with biological exploration and a first-contact story with some quite-alien aliens. This is the sort of novel where the protagonist's culture is as foreign to the reader as any of the other cultures he counters, so the reader is assembling several jigsaw puzzles at once. John is dropped into an established colony with its own social norms and established hierarchies. The one other outsider, the translator Sudharma Jain, is, as his name implies, a Jain who keeps very strict religious observances. Half of the colony is from something akin to a fundamentalist Christian religious sect that practices patriarchy and strict marriage codes. The other half is more gently sexist (but still sexist) and has its own tradition of a third gender that becomes central to the story. John, meanwhile, is a strong believer in the Essian approach to social organization: Any two partners of any gender freely have sex by mutual consent and without obligation, and family is based solely on blood relations. These beliefs do not fit comfortably together, even when people are trying (as they mostly do) to be welcoming. The first half of this book is very slow. This gives all of the characters space to breathe and become comfortable, and the characterization is superb, but it is a book to start when you're in the mood for something slow and observational. There is a plot that gradually becomes apparent, or rather there are several plots that are intertwined, but tension and urgency are mostly reserved for the second half of the book. Instead, the book opens with a lot of close observation of alien flora and fauna and the untangling of subtle social dynamics among the Scythians. There is also a visitor from earth, much to the distress of the Scythians. Earth presence means the ships will not return and the colony may be cut off from any sort of technological resupply. Despite speaking a common language, that visitor is as mutually alien to the other groups as they are to the native flora. Her life is fully integrated with aiyis, giving her essentially godlike powers and the ability to turn off inconvenient emotions and disregard anything she doesn't want to see. What she and the Earth aiyis are doing on the planet is one of the early mysteries. The dialogue in this book is truly excellent. Each characters has their own voice, there are fascinating digressions on different words that lead to tidbits of world-building, and some of the culture-specific idioms are delightful.
"I'm making a mess of this. None of that matters. Let me fall out the window and come in the door again. This is how my story ought to start:"
The challenges for the characters in this story are slow but deep ones: belonging and self-definition, the conflict between cultural tradition and personal circumstance, and the sacrifices required to live with small groups in situations where civil war is viscerally attractive. It has one of the most comprehensive and fascinating treatments of transgender issues that I've read in science fiction. Its commentary on current politics is subtle and estranged in the way that science fiction does best, but still pointed and satisfying. And, well, there are passages like this that I absolutely adore:
"I wouldn't go that far. It could be they are right, the universe we see exists because a mind like ours created it at least, a mind enough like ours that we can say it wants one thing and not another, and when it acts it does so with intent. That's as good an idea as any. But it is certainly not plausible that such a being believes that people everywhere should marry, or that men should never visit men, or no one should become a jess. Look at what they have created. The universe could have been nothing at all, or one atom of hydrogen floating in a void, or a diamond crystal infinite in all directions, if their mind cared for simplicity or tidiness. Instead we have stars and planets and black holes and nebulas. It could have all been cold and dead, but there is life. They could have made one species for each world, or just a few, which could have stayed the same forever, but instead we have millions and millions, all of which are changing every moment, varying among themselves and boiling off in all directions. Such a god is like an artist who fills up a library of sketchbooks with their drawings of strange creatures, and when every scrap of paper in the place is used up, goes back with a different color ink and scribbles over them again. They are obsessed with variation they gorge themselves with it and never grow full. Do you really think a mind like that could want us all to live in the same way?"
I had one problem with this book, though, and for me it was a big one: There is no ending. Reed effectively builds tension, gets me caring about all of the characters, sets up several problems, starts down a path towards resolution, and then the book just... ends. Long-time readers of my reviews will know that I'm a denouement fanatic. I want the scouring of the shire, I want the chapter set in the happily ever after, I want the catharsis of an ending. This made me so grumpy! To be clear, this is not sequel bait (at least so far as I can tell). I can write a philosophical defense of the ending. The types of problems and lives that Reed set up don't have clear endings; this is, to some extent, the point. We muddle through, and then those who come after us muddle through some more, and the cumulative effect is called human civilization. And there is some denouement; Reed doesn't leave the reader at a cliffhanger or anything that egregious. But still, I wanted the happy ending, even though that was unrealistic for the style of story this is, because I'm a happy ending reader. This is not an ending sort of book; it's the sort of book where I get a sinking feeling at the 95% mark because there aren't enough pages left for the number of remaining unresolved problems. I've gotten less annoyed in the days since I finished the book, and I can appreciate the thematic point made by how the book ends, but I still feel like it's worth an advance warning if you're a reader like I am. I would be delighted by a sequel, but it didn't feel like that was the intent. Apart from that, this was both excellent and rather unlike a lot of current science fiction. I think the closest comparison I can make among recent novels I've read is Sue Burke's Semiosis. What We Are Seeking has a similar sort of world-building, but I liked these characters so much more. It felt like a classic literary science fiction novel, but very much written in 2026. Highly recommended, just beware of the lack of closure. Content notes: Sexism, homophobia, stomach illness, and some religious abuse. Rating: 8 out of 10

25 April 2026

Russ Allbery: Review: The Genocidal Healer

Review: The Genocidal Healer, by James White
Series: Sector General #8
Publisher: Orb
Copyright: 1991
Printing: May 2003
ISBN: 0-7653-0663-8
Format: Trade paperback
Pages: 255
The Genocidal Healer is the eighth book in James White's medical science fiction series about the Sector General hospital. As with the rest of the series, detailed memory of the previous books is not required and the books could be read out of order if you didn't mind spoilers. I read this as part of the Orb General Practice omnibus. Surgeon-Captain Lioren is a Tarlan doctor who was in charge of the medical response to a newly-discovered civilization. The aliens were suffering from an apparently universal plague and an ongoing vicious war waged entirely through hand-to-hand combat, putting them on the edge of extinction. Lioren rushed the distribution of a possible cure against the advice of the doctors working on developing it, with catastrophic results. As The Genocidal Healer opens, Lioren is insisting on a court-martial in the hope of receiving the sentence it believes it deserves and was denied: death. (It pronouns are the convention in the Sector General series for all alien races and formal discussions, because even someone prone to bouts of gender essentialism such as White understood the need for avoiding gender assumptions in a science fiction medical context.) Predictably, both Sector General and the Monitor Corps that technically runs the hospital are flatly unwilling to execute Lioren. Instead, he is assigned as a new apprentice in the psychology department under the legendary O'Mara, where he is ordered to investigate the psychological fitness of a senior doctor named Seldal. This leads him to talk to Seldal's patients, which in turn leads to a challenging set of ethical dilemmas. The first five chapters (and more than sixty pages) are the story of Lioren's trial and a recounting of the events on Cromsag. The series is full of medical and cultural puzzles like this, and usually I like them, but I thought this one was less successful. We know the vague (and horrible) outline of the ending in advance, and the massive simplification and artificial universality that is required to make this puzzle work is particularly blatant. A universally infectious disease is more of a fiction plot than a believable biological concept, and the number of failures of communication, analysis, and misunderstanding that have to line up to create White's predetermined outcome were a bit much for me. Once the story gets past that and into Lioren's psychological work, the novel improves. Lioren is guilt-ridden and irrational, but also rather arrogant about his guilt and his concepts of professional responsibility in a way that I think mostly worked. Most of the novel consists of Lioren slowly discovering that people like him and enjoy talking to him, much to his bafflement. In that, it has the gentle kindness and sense of universal basic decency that is characteristic of this series. There are, of course, medical puzzles to solve, although this time they are primarily psychological in nature. Various characters from previous books make an appearance, but White re-explains their background in sufficient detail that you don't need to remember (or have read) those previous books. There are a lot of similarities between this book and the previous one, Code Blue Emergency. Both feature nonhuman viewpoint protagonists and amusing descriptions of human facial expressions from an alien perspective. Both feature protagonists with overly rigid ethical structures that partly clash with the generally human policies of Sector General. The Genocidal Healer is a bit more subtle and nuanced, although a lot of Lioren's psychological evaluation rests on an ethical difference that I found somewhat unbelievable. This book, though, tackles a subject the previous book did not: religion. The treatment isn't horrible, but I have some complaints. My primary issue is that Lioren, who starts as an atheist, does extensive research into religion to help a patient and then starts making statements summarizing the religions beliefs of the majority of known species that are just... Christianity. As someone raised Christian, I recognized it immediately as the sort of abstracted Christianity that Christians claim is universal while completely ignoring the opinions of the adherents of any other religion. Key components of this majority galactic religious pattern, according to Lioren, include an omnipotent and omnibenevolent creator god, a religious figure who preaches forgiveness and mercy and is persecuted, and emphasis on redemption. This simply is not some abstract universal religion. This is just Christianity in disguise. Even in religions that have some of those elements in their traditions, they do not get the same emphasis and are not handled the way that Lioren describes them. I therefore found Lioren's extended discussions of religion rather annoying, since he kept claiming as relatively universal principles beliefs that are not even held by the majority of religious adherents on Earth, let alone a wildly varying collection of alien races with entirely different biology and societal constructions. It caused a lot of problems for my suspension of disbelief, on top of the annoyance at this repetition of, frankly, Christian propaganda. Lioren goes, from that research, into theodicy (the problem of evil). The interesting part of this is White's earnest portrayal of a doctor's approach to societal problems: a desire to find workarounds and patches and fixes for anything that makes people unhappy, whether medical or social. It makes sense, given the horrible biologic hands that some of the aliens in this series have been dealt, that they would question the idea of a benevolent god, so this philosophical digression is justified in that sense. But you might guess that a mid-list science fiction author is not going to say something new about one of the oldest problems in Christianity, and indeed he does not. Lioren arrives at the standard handwaving about the unknowability of divine intent, which I found tedious to read but at least not fatal to the plot. White, thankfully, doesn't take the religious material too far. The characters recognize how sensitive of an issue religion is in a hospital, Lioren never adopts religion fully, and the resolution of the plot is as much biological as philosophical. White is going somewhere with the introduction of religion, and although some of the path there annoyed me, I think the destination worked. White was from Northern Ireland, and therefore well aware of the drawbacks of religion, and he abhorred violence (hence Sector General as a setting), so the reader is in better hands with him than with most authors who might attempt this plot. I think I know a bit too much about religion to be the best audience for this entry in the series, and I'm not sure the introductory five chapters quite worked. But as with all of the other books in the series, this kept me turning the pages and I'm glad I read it. The Genocidal Healer probably isn't worth seeking out unless you're reading the whole series, but if you're enjoying the rest of the series, you'll probably like this too. Followed by The Galactic Gourmet. Rating: 6 out of 10

23 April 2026

Sergio Talens-Oliag: Developing a Git Worktree Helper with Copilot

Over the past few weeks I ve been developing and using a personal command-line tool called gwt (Git Worktree) to manage Git repositories using worktrees. This article explains what the tool does, how it evolved, and how I used GitHub Copilot CLI to develop it (in fact the idea of building the script was also to test the tool).

The Problem: Managing Multiple BranchesI was working on a project with multiple active branches, including orphans; the regular branches are for fixes or features, while the orphans are used to keep copies of remote documents or store processed versions of those documents. The project also uses a special orphan branch that contains the scripts and the CI/CD configuration to store and process the external documents (it is on a separate branch to avoid mixing its operation with the main project code). The plan is trigger a pipeline against the special branch from remote projects to create or update the doc branch for it in our git repository, retrieving artifacts from the remote projects to get the files and put them on an orphan branch (initially I added new commits after each update, but I changed the system to use force pushes and keep only one commit, as the history is not really needed). The original documents have to be changed, so, after ingesting them, we run a script that modifies them and adds or updates another branch with the processed version; the contents of that branch are used by the main branch build process (there we use git fetch and git archive to retrieve its contents). When working on the scripts to manage the orphan branches I discovered the worktree feature of git, a functionality that allows me to keep multiple branches checked out in parallel using a single .git folder, removing the need to use git switch and git stash when changing between branches (until now I ve been a heavy user of those commands). Reading about it I found that a lot of people use worktrees with the help of a wrapper script to simplify the management. After looking at one or two posts and the related scripts I decided to create my own using a specific directory structure to simplify things. That s how I started to work on the gwt script; as I also wanted to test copilot I decided to build it using its help (I have a pro license at work and wanted to play with the cli version instead of integrated into an editor, as I didn t want to learn a lot of new keyboard shortcuts).

The gwt Philosophy: Opinionated and Transparentgwt enforces a simple, filesystem-visible model:
  • Exactly one bare repository named bare.git (treated as an implementation detail)
  • One worktree directory per branch where the directory name matches the branch name
  • Single responsibility: gwt doesn t try to be a general git wrapper; it only handles operations that map cleanly to this layout
The repository structure looks like this:
my-repo/
+-- bare.git/           # the Git repository (internal)
+-- main/               # worktree for branch "main"
+-- feature/api/        # worktree for branch "feature/api"
+-- fix/docs/           # worktree for branch "fix/docs"
+-- orphan-history/     # worktree for the "orphan-history" branch
The tool follows five core design principles:
  1. Explicit over clever: Git commands are not hidden or reinterpreted
  2. Transparent execution: Every operation is printed before it happens
  3. Safe, preview-first operations: Destructive commands default to preview, confirmation, then apply
  4. Shell-agnostic core: The script never changes the caller s working directory (shell wrappers handle that)
  5. Opinionated but minimal: Only commands that fit the layout model are included

Core CommandsThe script provides these essential commands:
  • gwt init <url> Clone a repository and set up the gwt layout
  • gwt convert <dir> Convert an existing Git checkout to the gwt layout
  • gwt add [--orphan] <branch> [<base>] Create a new worktree (optionally orphaned)
  • gwt remove <branch> Remove a worktree and unregister it (asks the user to remove the local branch too, useful when removing already merged branches)
  • gwt rename <old> <new> Rename a branch AND its worktree directory
  • gwt list List all worktrees
  • gwt default [<branch>] Get or set the default branch
  • gwt current Print the current worktree or branch name
Except init and convert all of the commands work inside a directory structure that follows the gwt layout, which looks for the bare.git folder to find the root folder of the structure. As I don t want to hide which commands are really used by the wrapper, all git and filesystem operations pass through a single run shell function that prints each command before executing it. This gives complete visibility into what the tool is doing. Also, destructive operations (remove, rename) default to preview mode:
$ gwt remove feature-old --dry-run
+ git -C bare.git branch -d feature-old
+ git -C bare.git worktree remove feature-old/
Apply these changes? [y/N]:
The user sees exactly what will happen, can verify it s correct, and only then confirm execution.

Incremental Development with CopilotThe gwt script has grown from 597 lines in its original version (git-wt) to 1,111 lines when writing the first draft of this post. This growth happened through incremental, test-driven development, with each feature being refined based on real usage patterns. What follows is a little history of the script evolution written with the help of git log.

Initial versionFirst I wrote a design document and asked copilot to create the initial version of the git-wt script with the original core commands. I started to use the tool with a remote repostory (I made copies of the branches in some cases to avoid missing work) and fixed bugs (trivial ones with neovim, larger ones asking copilot to fix the issues for me, so I had less typing to do).

First command updateOne of the first commands I had to enhance was rename:
  • as I normally use branches with / on their name and my tool checks out the worktrees using the branch name as the path inside the gwt root folder (i.e. a fix/rename branch creates the fix directory and checks the branch inside the fix/rename folder) the rename command had to clean up the empty parent directories
  • when renaming a worktree we move the folders and fix the references using the worktree repair command to make things work locally, but the rename also affects the remote branch reference, to avoid surprises the command unsets the remote branch reference so it can be pushed again using the new name (of course, the user is responsible of managing the old remote branch, as the gwt can t guess what it should do with it).

Integration with the shellAs I use zsh with the Powerlevel10k theme I asked copilot to help me add visual elements to the prompt when working with gwt folders, something that I would have never tried without help, as it would have required a lot of digging on my part on how to do it, as I never looked into it. The initial version of the code was on an independent file that I sourced from my .zshrc file and it prints on the right part of the prompt when we are inside a gwt folder (note that if the folder is a worktree we see the existing git integration text right before it, so we have the previous behavior and we see that it is a gwt friendly repo) and if we are on the root folder or the bare.git folder we see gwt or bare (I added the text because there are no git promts on those folders). I also asked copilot to create zsh autocompletion functions (I only use zsh, so I didn t add autocompletion for other shells). The good thing here is that I wouldn t have done that manually, as it would have required some reading to get it right, but the output of copilot worked and I can update things using it or manually if I need to. One thing I was missing from the script was the possibility of changing the working directory easily, so I wrote a gwt wrapper function for zsh that intercepts commands that require shell cooperation (changing the working directory) and delegates everything else to the core script. Currently the function supports the following enhanced commands:
  • cd [<branch>]: change into a worktree or the default one if missing
  • convert <dir>: convert a checkout, then cd into the initial worktree
  • add [--orphan] <branch> [<base>]: create a worktree, then cd into it on success
  • rename <old> <new>: rename a worktree, then cd into it if we were inside it
Note that the cd command will not work on other shells or if the user does not load my wrapper, but the rest will still work without the working directory changes.

Renaming the commandAs I felt that git-wt was a long name I renamed the tool to gwt, I could have done it by hand, but using copilot I didn t have to review all files by myself and it did it right (note that I have it configured to always ask me before doing changes, as it sometimes tries to do something I don t want and I like to check its changes as I have the files in git repos, I manually add the files when I like the status and if the cli output is not clear I allow it to apply it and check the effects with git diff so I can validate or revert what was done).

The convert commandAfter playing with one repo I added the convert subcommand for migrating existing checkouts, it seemed a simple task at first, but it took multiple iterations to get it right, as I found multiple issues while testing (in fact I did copies of the existing checkouts to be able to re-test each update, as some of the iterations broke them). The version of the function when this post was first edited had the following comment explaining what it does:
# ---------------------------------------------------------------------------
# convert - convert an existing checkout into the gwt layout
# ---------------------------------------------------------------------------
#
# Must be run from the parent directory of <dir>.
#
# Steps:
#   1. Read branch from the checkout's HEAD
#   2. Rename <dir> to <dir>.wt.tmp (sibling, same filesystem)
#   3. Create <dir>/ as the new gwt root
#   4. Move <dir>.wt.tmp/.git to <dir>/bare.git; set core.bare = true
#   5. Fix fetch refspec (bare clone default maps refs directly, no remotes/)
#   6. Add a --no-checkout worktree so git wires up the metadata and
#      creates <dir>/<branch>/.git (the only file in that dir)
#   7. Move that .git file into the real working tree (<dir>.wt.tmp)
#   8. Remove the now-empty placeholder directory
#   9. Move the real working tree into place as <dir>/<branch>
#  10. Reset the index to HEAD so git status is clean
#      (--no-checkout leaves the index empty)
#  11. Create <dir>/.git -> bare.git symlink so plain git commands work
#      from the root without --git-dir
#
# The .git file ends up at the same absolute path git recorded in step 5,
# so no worktree repair is needed. Working tree files are never modified.
The .git link was added when I noticed that I could run commands that don t need the checked out files on the root of the gwt structure, which is handy sometimes (i.e. a git fetch or a git log, that shows the log of the branch marked as default). After playing with commands that used the bare.git folder I updated the init and convert commands to keep the origin refs, ensuring that the remote tracking works correctly.

Improving the add commandWhile playing with the tool on more repos I noticed that I also had to enhance the add command to better handle worktree creation, depending on my needs. Right now the tool supports the following use cases:
  • if the branch exists locally or on origin, it just checks it out.
  • if the branch does not exist, we create it using the given base branch or, if no base is given, the current worktree (if we are in the root folder or bare.git the command fails).
  • as I needed it for my project, I added a --orphan option to be able to create orphan branches directly.

Moving to a single fileEventually I decided to make the tool self contained; I removed the design document (I moved the content to comments on the top of the script and details to comments on each function definition) and added a pair of commands to print the code to source for the p10k and zsh integration (autocompletion & functions), leaving everything in a single file. Now my .zshrc file adds the following to source both things:
# After loading the p10k configuration
if type gwt >/dev/null 2>&1; then
  source <(gwt p10k)
fi
[...]
# After loading autocompletion
if type gwt >/dev/null 2>&1; then
  source <(gwt zsh)
fi

VersioningAs I modified the script I found interesting to use CalVer-based versioning (the version variable has the format YYYY.mm.dd-r#) so I added a subcommand to show its value or bump it using the current date and computing the right revision number.

About the use of copilotAlthough I ve never been a fan of AI tools I have to admit that the copilot CLI has been very useful for building the tool:
  • Rapid prototyping: Each commit represented a small feature or fix that I could implement, test immediately in my actual workflow, and iterate on based on the result
  • Edge case handling: Rather than trying to anticipate every scenario upfront, I could ask Copilot how to handle edge cases as they appeared in real usage
  • Script refinement: Questions like "how do I clean up empty directories after a rename" or "how do I detect if I m inside a specific worktree" were quickly answered with working code
  • Shell integration: The Zsh wrapper and completion system grew from simple prototypes to sophisticated features, with each iteration informed by how I actually used the tool
For example, the convert command started as a simple rename operation, but evolved to also create a .git symlink and intelligently handle various migration scenarios all because I used it repeatedly and refined the implementation each time.

Self-Contained and Opinionatedgwt is deliberately opinionated:
  • Zsh & Powerlevel10k Integration: The tool includes built-in Zsh shell integration, accessed via source <(gwt zsh) and supports adding a prompt segment when using p10k, as described earlier.
  • Directory Structure: The bare.git directory name is non-negotiable. This is how gwt discovers the repository root from any subdirectory, and how the tool knows whether a directory is a gwt repository. The simplicity of this marker means the discovery mechanism is foolproof and requires no configuration.
  • No Configuration Files: gwt deliberately has no configuration. There are no .gwtrc files or config directories. This makes it portable; the tool works the same way everywhere, and repositories can be shared across systems without synchronizing configuration.

From Script to SystemWhat started as a small helper script for managing worktrees has become a complete system:
  1. Core script (gwt): 1,111 lines of pure shell, no external dependencies
  2. Shell integration: Zsh functions and completions
  3. Prompt integration: Powerlevel10k segment
  4. Documentation: Built-in help and design philosophy documentation
The script is self-contained, everything needed for the tool to work is in a single file. This makes it trivial to update (just replace the script) or audit (no hidden dependencies).

Development with AI supportDeveloping gwt with copilot taught me some things:
  • Incremental refinement works well for small tools: Each iteration informed the next, resulting in a tool that handles real use cases elegantly
  • Transparency is a feature: Making operations visible builds confidence and is easier to debug
  • Opinionated tools can be powerful: By constraining the problem space (one bare repo, one worktree per branch), the solution becomes simpler and more robust
  • Shell integration matters: The same core commands are easier to use when they can automatically change directories and provide completions
  • Real-world testing is essential: I wouldn t have discovered the need for automatic directory cleanup or context-aware cd behavior without actually using the tool daily

What was next?The tool is stable and handles my daily workflow well, so my guess is that I would keep using it and fixing issues if or when I found them, but I do not plan to include additional features unless I find a use case that justifies it (i.e. I never added support for some of the worktree subcommands, as it is easier to use the git versions if I ever needed them).

What really happenedWhile editing this post I discovered that I needed to add another command to it and fixed a bug (see below). With those changes and the inclusion of a license and copyright notice (just in case I distribute it at some point) now the script is 1,217 lines long instead of the 1,111 it had when I started to write this entry.

Submodule SupportWhen I converted this blog repository to the gwt format and tried to preview the post using docker compose, it failed because the worktree I was on didn t have the Git submodule initialized. My blog theme is included on the repository as a submodule, and when I used gwt to check out different branches in worktrees, the submodule was not initialized in the new worktrees. This led me to add new internal function and a gwt submodule command to handle submodule initialization; the internal function is called from convert and add (when converting a repo or adding a worktree) and the public command is useful to update the submodules on existing branches.

Path Handling with Branch Names Containing SlashesThe second discovery was a bug in how the tool handled branch names containing slashes (e.g., feature/new-api, docs/user-guide), the worktree directories are created with the branch name as the path, so a branch like feature/new-api would create two nested folders (feature and new-api inside it). However, there was a mismatch in how the zsh wrapper function resolved worktree paths (initially it used shell parameter expansion, i.e. rel="$ cwd#"$REPO_ROOT"/ "), versus how the core script calculated them, causing the cd command to fail or navigate to the wrong location when branch names contained slashes. The fix involved ensuring consistent path resolution throughout the script and wrapper (now it uses a function that processes the git worktree list output), so that gwt cd feature/new-api correctly navigates to the worktree directory regardless of path depth.

Conclusiongwt is a tool that solves a real problem: managing multiple Git branches simultaneously without context-switching overhead. I m sure I m going to keep using it for my projects, as it simplifies some workflows, although I ll also use switch and stash in some cases, but I like the use of multiple worktrees in parallel. In fact I converted this blog repository checkout to the gwt format to work on a separate branch as it felt the right approach even if I m the only one using the repo now, and it helped me improve the tool, as explained before. Also, it was a good example of how to use AI tools like copilot to develop a simple tool and keep it evolving while using it. In any case, although I find the copilot useful and has saved me time, I don t trust it to work without supervision, it worked well, but got stuck some times and didn t do the things as I wanted in multiple occasions. I also have an additional problem now I ve been reading about it, but I don t really know which models to use or how the premium requests are computed (I ve only been playing with it since last month and I ran out of requests the last day of the month on purpose, just to see what happened it stops working ;). On my work machine I ve been using a specific user account with a GitHub Copilot Business subscription and I only used the Anthropic Claude Sonnet 4.6 model and with my personal account I configured the Anthropic Claude Haiku 4.5 model, but I ve only used that to create the initial draft of this post (I ended up rewriting most of it manually anyway) and to review the final version (I m not a native speaker and it was useful for finding typos and improving the style in some parts). I guess I ll try other models with copilot in the future and check other command line tools like aider or claude-code, but probably only using free accounts unless I get a payed account at work, as I have with GitHub Copilot. To be fair, what I will love to be able to do is to use local models (aider can do it), but the machines I have are not powerful enough. I tried to run a simple test and it felt really slow, but when I have the time or the need I ll try again, just in case.

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