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Let me recall the game. Peter tosses a coin until it lands heads. If heads comes up on the first toss, Peter pays Paul 1 ducat, on the second 2, on the third 4, and every further toss doubles the payout. The average of this game is infinite, yet no reasonable person will pay twenty ducats for it. That is the first of the four paradoxes from the first part.

The last of the four was about Peter rather than Paul. To run the game, Peter has to promise any payout: heads on the 41st toss, for example, means more than a trillion ducats, 17 times all the gold ever mined. In 1977 the American mathematician Lloyd Shapley titled a paper about this as a question: «The St. Petersburg Paradox: A Con Game?»

Can the St. Petersburg game be run honestly? Nobody can honestly promise an unlimited payout, but Peter can promise a share of the bank instead of a sum: then the promise never exceeds what the bank holds, and the bank does not go bankrupt. We will go step by step through how this works and what happens to each paradox, starting with the fourth: it gives us the bank on which the other sections are built. A fifth paradox will appear along the way.

Students increasingly use LLMs to write essays, term papers, theses — any assignment that isn't done under an instructor's continuous supervision. Naturally, the higher education system is unhappy about this and is trying to fight back. And the simplest solution is to detect AI-generated texts and reject them.

This article is about the non-obvious ways AI detectors affect education.

Or why ten users can teach you more than a thousand GitHub stars.

Let me start with a strong opinion: at any company with more than three or four people, local agent harnesses should be banned. Maybe confiscate the developer’s keyboard while you’re at it.

A local harness is a great way to indulge a programmer’s ego, lose everything they’ve learned when they leave, waste hours setting up MCP servers, services, and development environments all over again — and eventually let an agent do something spectacularly stupid on a machine where it has local administrator privileges.

The problem is that there are hardly any mature, multi-tenant harnesses available off the shelf. And the few options that exist often require assembling a complicated system from separate parts.

My hobby projects are small Chrome extensions and little single-purpose websites. One of those extensions, PDF to PNG, unexpectedly climbed to first place in Chrome Web Store searches for “pdf to png” (well, most of the time), and nearly 500 people use it - which is amazing!

Once PDF to images worked, I immediately wanted to do the reverse - images -> PDF, only better: right-click an image on any page, have an easy(!) way to adjust the settings, and do everything locally in the browser without uploading the images anywhere!

For every AI workflow we define, the next model makes it useless.

What’s worse: most of us keep clinging to the outdated workflows for months after they’ve outlived their usefulness.

Two people are playing: Peter and Paul. Peter tosses a coin until it lands heads. If heads comes up on the first toss, Peter pays Paul 1 ducat. If on the second, 2 ducats. If on the third, 4 ducats. And so on: every toss without heads doubles the payout. Paul pays Peter in advance for the right to play. This is the form in which Daniel Bernoulli studied the game in his paper of 1738.

Imagine that Paul is you. How much would you pay Peter for a single game? Answer right away, in ducats, and remember your answer: you will need it at the end of the article. For now, let us assume that 1 ducat equals $10. What a ducat is really worth is in the spoiler after the first paradox.

18th-century mathematicians calculated the price of this game by correct rules and got an answer they themselves found absurd. This is the paradox. The dispute over where the error lies lasted almost three hundred years and led to three more paradoxes. Four future Nobel laureates took part in it.

A recently published research essay claims that the difficulty of neural network interpretability has been overstated. In his essay on goodfire.com, Nick Cammarata argues that neuron polysemanticity is caused not by superposition but by ordinary, mostly fixable issues — and that most neurons, even in massive models, perform a single, understandable job. The author himself calls the text a working hypothesis: the technical paper with a full description of the experiments has not been released yet. However, as usual, a bold headline and strong claims have sparked numerous retellings in which the hypothesis has turned into established fact.

Below is a quick look at this hypothesis.

Eight agencies ranked by real results, from ICODA and Coinbound to dev-plus-marketing hybrids built for early-stage founders.

In Axia 0.1.0, a user allowed to edit accounts and move OUs could reset an administrator’s password in four requests. None of the four broke the rule written to prevent exactly that.

Axia is an open-source web console and REST API for Active Directory and OpenLDAP (.NET 10, React). It exists for a routine every company with a directory knows: create an account, reset a password, add someone to a group, disable a leaver. That work belongs with helpdesk, but helpdesk must not be able to promote itself, and every action must leave a trace.

This is not a feature tour. It is five places where the obvious implementation turned out to be a hole or a bug, and what fixed each one. Most of them have nothing to do with Axia: anyone who builds access control on top of LDAP will run into them.

If you’re looking to set up 10-channel audio output at a 192 kHz sample rate using a MCU, read on. This article explains how to implement multi-channel audio on an RP2040 using an ALC889 HD audio codec. It includes a brief overview of the HDA link interface, along with links to a couple of functional demo projects and descriptions of how they work.

We’re wrapping up our review of the March CommitFest for PostgreSQL 19. This fourth and final article in the series covers the changes related to SQL and to our DEV1 and DEV2 courses.

As a reminder, here’s the plan for our coverage of the final PostgreSQL 19 CommitFest:

Part 5.1 (QPT)

Part 5.2 (DBA1, DBA2)

Part 5.3 (DBA3, DBS)

Part 5.4 (SQL, DEV1, DEV2) – you are here 🙂

For the earlier CommitFests, see: 2025-07, 2025-09, 2025-11, 2026-01.

In school, they teach you that you can’t divide by zero. Then you study calculus and discover that things are more complicated. The same goes for game design. Some teachings sound obvious until you look at them more closely.

Healthcare app development has skyrocketed in recent years, establishing itself as one of the most critical sectors in mobile product design. The demand surged dramatically with the start of the pandemic in 2020 when safety concerns forced the mass cancellation of in-person appointments, driving an abrupt shift toward remote consultations. Today, with the global market value surpassing $300 billion and annual downloads exceeding 300 million, the competition is incredibly fierce. Apart from that, healthcare apps are considered to be among the most complex and challenging software products to build from a UX design perspective. Launching a basic app is no longer enough – you must deliver a flawless, high-performance product that seamlessly caters to a diverse range of users, including patients of all ages and of different health conditions, doctors of various specialities and administrative staff. Above all, a premium healthcare app demands an impeccable interface that strictly adheres to both medical design principles and rigid digital health regulations. 

In this guide we’ve collected the core principles of healthcare UX, along with the typical challenges designers face and the key mistakes to watch out for.  

I wanted to buy Telegram Stars for less, so I compared the same packages on three websites. SMMESE had the lowest listed price of the three: $15.31 for 1,000 Stars, compared with $16.50 on TgSuperstars and $16.67 on MyStars.tg.

I then traced how a service finds the recipient, pays from its own wallet, and confirms the order. The Python implementation below can become the part of your own Stars website that fulfills purchases.

We’re continuing our review of the March CommitFest for PostgreSQL 19. This third article in the series covers the changes related to our DBA3 and DBS courses.

As a reminder, here’s the plan for our coverage of the final PostgreSQL 19 CommitFest:

Part 5.1 (QPT)

Part 5.2 (DBA1, DBA2)

Part 5.3 (DBA3, DBS) – you are here 🙂

Part 5.4 (SQL, DEV1, DEV2)

For the earlier CommitFests, see: 2025-07, 2025-09, 2025-11, 2026-01.

I have a Flydigi Vader 5 Pro controller and its Charging Dock 2 Pro. The dock has 162 RGB LEDs, and the LEDs themselves are good, but the effects in Flydigi's Space Station app look cheap: slow animations step, gradients turn muddy in the middle.

I wondered whether the hardware or the software was to blame. Spoiler: the software. I figured out how the dock receives frames, rewrote the effects from scratch and made my own lighting editor.

We’re continuing our review of the March CommitFest for PostgreSQL 19. This second article in the series covers the changes related to our DBA1 and DBA2 courses.

As a reminder, here’s the plan for our coverage of the final PostgreSQL 19 CommitFest:

Part 5.1 (QPT)

Part 5.2 (DBA1, DBA2) – you are here 🙂

Part 5.3 (DBA3, DBS)

Part 5.4 (SQL, DEV1, DEV2)

For the earlier CommitFests, see: 2025-07, 2025-09, 2025-11, 2026-01.

We’re wrapping up our series of articles reviewing the changes in PostgreSQL 19. The previous articles covered the first four CommitFests: 2025-07, 2025-09, 2025-11, 2026-01.

Today we begin our review of the March 2026 CommitFest. Why «begin»? As in previous years, the March review is going to be a long one: the final CommitFest of the cycle is where many of the most important changes land. Such a review is hard not only to write but also to read all the way through 🙂. That’s why this time it’s split into four articles.

The first article covers everything related to query optimization, in other words, the topics of our QPT training course. The second will focus on changes more relevant to the DBA1 and DBA2 courses. The third will cover DBA3 and DBS. The fourth will look at new SQL features, as well as changes related to the DEV1 and DEV2 courses.

Codex Cloud runs coding tasks in a remote environment. You can ask it to explain a project, edit files, run checks, and prepare a GitHub pull request while your computer is asleep.

It was late in the evening. I had a splitting headache, a nasty cold made it hard to breathe, and the thermometer was stubbornly creeping upward. What can you even do in a state like that, when it feels like the Grim Reaper is right around the corner, already waxing its skis?