Solution to Feynman's reverse sprinkler puzzle also applies to "silly sprinklers"
New study confirms 2024 "momentum flux theory" on how angular momentum of water flows drives rotation.
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New study confirms 2024 "momentum flux theory" on how angular momentum of water flows drives rotation.
Startle the snake by striking the grass. — The 36 Stratagems, Stomp the Grass to Scare the...
A team lead announces that the team will start using AI-assisted development. Everyone nods. Nobody asks what that actually means on Monday morning. Some times ago I was in that position. A project I was working on needed to start using AI-assisted development, and the team was new to it. Nobody had rules written down for an agent to follow. Nobody had skills defined for it to load. There was no shared idea of how this should work inside our specific repo. Someone had to go first. That someone was me. The rules worked because I built them for one repo I spent time curating a set of rules and skills for that project. Not generic ones. I shaped them tightly around how that repo was actually structured, its conventions, its layout, the things a new engineer usually has to learn by asking around. I wanted an agent working inside that codebase to already know what a human teammate would have picked up in the first two weeks. I gave a demo. It landed well. Well enough that it got shared further across team, as something other teams could learn from. I gave the demo again. Same reaction. Then a few developers reached out for the actual rules and skills files. I said sure, and then I actually looked at what I would be handing them. The problem showed up the moment other people wanted in It was not copy-paste-able. The rules referenced folder names, module boundaries, and patterns specific to one repo. Handing them over as-is would have meant handing over advice that was wrong for their project, dressed up as a shortcut. So I told them to use it as a reference. Look at the structure, understand the reasoning, adapt it to your own repo. That is correct advice. I watched people nod at it and then quietly missing it. I was solving the wrong problem the whole time I had been thinking about this as a documentation problem. Write good rules, explain them well, let people copy the idea. What I actually had was a generation problem. The rules that worked were the ones rendered speci
I didn’t set out to diagnose hyperscalers. I wasn’t doing a grand industry analysis. I wasn’t mapping global architecture. I wasn’t trying to understand cloud strategy. I was just trying to use a popular software provider — and everything kept breaking. Every time something failed, I followed the thread. And every thread led to the same architectural gap. Eventually I realised I hadn’t been analysing hyperscalers at all. I’d accidentally mapped the substrate failure across the entire industry. Once you see the pattern, you can’t unsee it. Across Microsoft, AWS, Google, and Meta, the same structural drift appears: meaning drift identity drift trust drift state drift execution drift provenance drift agentic drift Different companies. Different stacks. Different histories. Same substrate gap. And it’s not just me. The world is waking up to these problems too. Vendor lock in isn’t just a technical nuisance anymore — it’s becoming a public conversation. People are asking why their money keeps disappearing into the same handful of providers. Organisations are asking why their systems collapse the moment they try to leave. Governments are asking why critical infrastructure depends on architectures they cannot inspect, cannot govern, and cannot reproduce. What started as a personal frustration with a popular software provider turns out to be the same structural issue everyone else is now discovering. And sovereignty is entering the conversation — not as a political slogan, but as an architectural question. When national systems depend on fragmented substrates owned by a tiny cluster of vendors, sovereignty becomes a structural issue. The question isn’t “who controls the cloud?” It’s “who controls the substrate the cloud is built on?” Follow the thread far enough and you reach a scenario nobody wants to think about: what happens in a moment of global stress when a hyperscaler’s fragmented substrate becomes a single point of failure? Not a political crisis — a structural one.
How I Built CodeGraph: A Living Knowledge Graph That Tells You What Breaks Before You Break It Built for HACKHAZARDS '26 — powered by Neo4j AuraDB, tree-sitter, Groq LLaMA, and Next.js The Problem That Frustrated Me Every developer knows this feeling. You join a new codebase. There are 50,000 lines of code. Your manager says "just fix this small bug in the authentication module." You make the change. You push. And suddenly three completely unrelated features are broken — a payment flow, a notification system, and a dashboard widget you've never even looked at. You spend the next four hours tracing function calls manually, reading code you've never seen, trying to understand why changing one function in auth.py broke something in notifications.py on the other side of the codebase. This is not a rare experience. According to JetBrains' developer survey, engineers spend 58% of their time reading and understanding code — not writing it. One wrong change in a large codebase can cost hours of debugging, failed deployments, and frustrated users. I built CodeGraph to solve this. Not with another AI chatbot that guesses at your code. With a real, queryable knowledge graph that actually understands how your codebase is connected. What CodeGraph Does CodeGraph takes any public GitHub repository URL and within seconds: Parses every function in the codebase using tree-sitter Maps every call relationship between functions as a directed graph Stores everything in Neo4j AuraDB as a live knowledge graph Lets you ask questions in plain English — answered by AI grounded in real graph data The result: paste a GitHub URL, see your entire codebase as an interactive graph, click any function, and instantly know what breaks if you change it. The Tech Stack Here's what I used and why each choice mattered: Backend: Python + FastAPI (REST API server) Neo4j AuraDB (graph database — the core of everything) tree-sitter (AST parser for Python, JS, TS, TSX) Groq API with LLaMA 3.3 70B (free-tier L
Welcome back to The Everyday Backend Engineer: Practical Design Patterns . In our last post, we made our core algorithms interchangeable using the Strategy Pattern. Today, we close out our design patterns roadmap with arguably the most native pattern in the entire Node.js ecosystem: The Observer Pattern . Let’s look at how to master event-driven decoupling to trigger secondary workflows seamlessly without bloat. 🔴 The Problem: Direct Inline Side-Effects Imagine you are writing a video processing engine or a simple order fulfillment system. When a specific event happens—such as an order being finalized—multiple unrelated departments want a piece of the action: The Notification Service needs to send an SMS and Email receipt. The Logistics Service needs to generate a warehouse fulfillment ticket. The Analytics Service needs to update marketing tracking boards. If you don't decouple these events, your primary execution service ends up managing a giant web of secondary micro-services: // ❌ Bad Practice: The primary service is drowning in secondary dependencies const EmailService = require ( ' ../services/email ' ); const WarehouseService = require ( ' ../services/warehouse ' ); const AnalyticsTracker = require ( ' ../services/analytics ' ); class OrderProcessor { async finalizeOrder ( order ) { console . log ( " Saving primary order to the database... " ); // Core business logic ends here // The codebase smell: Procedural cascading dependencies await EmailService . sendReceipt ( order . userEmail ); await WarehouseService . createShipment ( order . id ); await AnalyticsTracker . trackSale ( order . totalAmount ); } } module . exports = OrderProcessor ; Why does this slow your system down? Your core OrderProcessor is now structurally dependent on three separate systems. If the AnalyticsTracker throws a network timeout error or if the warehouse API changes its interface, your core transaction fails or hangs. Furthermore, adding a fourth side-effect (like an auditing logger
A dozen state attorneys general are trying to block the $110 billion merger of Paramount and Warner Bros Discovery they warn would raise movie prices and crush cable TV distributors. The states - California, Arizona, Colorado, Connecticut, Massachusetts, Minnesota, Nevada, New Jersey, New Mexico, New York, Oregon, and Washington - filed suit on Monday, arguing […]
AG: Deal will bring "higher prices, lower quality, and less content for film and TV."
The failures that cost me the most in three years of self-hosting were never the ones that threw an error. An error is a gift: it tells you where to look. The expensive ones are the failures that report success while being broken . A page that returns 200 OK . A healthcheck that says the container is fine. A backup that exits cleanly. A command that prints nothing wrong. Everything green, everything lying. Here are four of them, all from the same box (a 2016 desktop, i7-6700 / 32 GB, Docker behind Caddy, reachable only over Tailscale). Each fails by handing you a success signal. Each cost me an evening the first time. The fixes are boring once you know them, the point is knowing the failure exists. Sanitized skeleton with all the config at the end. 1. A loading page that returns 200 This one I could find nothing written about, so it cost me the most. To keep the box quiet, I run the heavy services on-demand: Sablier stops idle containers and starts them on the first request. Caddy (with the Sablier plugin) gates a virtual host behind a container group, serves a "please wait, starting up" page while the group boots, then proxies through: myhost . my - tailnet . ts . net : 8081 { route { sablier http :// sablier : 10000 { group office session_duration 30 m } reverse_proxy nextcloud : 80 } } I gate my whole Nextcloud vhost, WebDAV included, this way. And here is the silent failure: if the gated group is not healthy, Sablier serves that HTML loading page for every request, and it serves it with 200 OK . A browser shows a spinner, fine. But my Obsidian vault syncs over WebDAV, and a WebDAV client asking for a directory listing got a 200 with a chunk of HTML instead of the XML it expected. Sync died with a cryptic no root multistatus found . Nextcloud itself was up and perfectly healthy the whole time. Every uptime check I had was green, because the gate in front kept answering 200 . The structural lesson: the moment you put a service on-demand behind a reverse proxy, tha
The two subscription services offer more than just extra storage, but getting the right one can save you money.
Why build something? And what if nobody ends up using it? There are good answers to the first one. You build because you need a thing that doesn't exist yet. You build to see if you can, the technical challenge, the "is this even possible?" You build to impress someone, or just because you think it'll make people's day a little less annoying. All of those are real reasons, and at different points, I told myself most of them. Then, a few days ago, late in the day, at the end of a coding session, five months into the project, I asked myself those two questions back-to-back. And for the first time, I couldn't answer the second one. Zeri worked. Every feature did what it was supposed to do. Both processes handshake cleanly, a variable set in one context showing up in another a second later, the TUI rendering exactly as I'd pictured it. And I sat there and couldn't come up with one honest sentence explaining why anyone would actually download it. That gap, between something built well and something that has a reason to exist, turned out to be the most useful thing this whole project taught me. So I'm shipping it anyway, and I'll tell you why. What I built Zeri is a TUI multi-language REPL. You launch it, pick a language, Python , JavaScript (with Bun ), Ruby , or LuaJIT , and you get an interactive session in your terminal. You can switch languages mid-session, share variables across them, save and reload your work, manage snippets, and talk to a local LLM through a command running on Ollama . The feature list isn't the interesting part, though. The interesting part is what's underneath. Two processes, one app Zeri is split into two processes: a headless engine written in C++23 and a TUI frontend built in Go using Bubble Tea and Lip Gloss . The engine does all the evaluation, state, and runtime coordination. The frontend does rendering, input, and everything the user actually sees and touches. They talk to each other over a custom binary IPC protocol that I built from sc
Yes-Brainer is a council of AI models for the decisions that aren't no-brainers. One question fans out to several models — they answer in parallel, debate to consensus, or get judged to a verdict. No backend, no accounts: your keys, your browser. For non-trivial questions — the ones that are either complex or important — I caught myself in a "ritual": copy-pasting the same prompt into Claude, then Gemini, then ChatGPT, in three browser tabs, and eyeballing the differences. The differences were the interesting part. Where the models agreed, I felt more confident. Where they disagreed, that was a nudge to give the problem a second thought and dig deeper. So I built the ritual into an app. 🧠 Yes-Brainer — a council of AI models for the decisions that aren't no-brainers. 🔗 Try it: yesbrainer.ai 🔗 Source code: github.com/trekhleb/yesbrainer One question fans out to several models at once, and instead of juggling tabs you get a deliberation in one place: 🔀 Parallel — independent answers, side by side ⚖️ Trial — the models vote anonymously on each other's answers, then a judge synthesizes a verdict 🤝 Consensus — a real multi-round debate, with a mediator that either drives it to convergence or honestly reports what stayed contested Consensus is my favourite. It's fun to watch the models drift from their original opinions under their peers' arguments. You can try all of this without pasting any keys: a few recorded demo councils are one click away on the front page. I'll walk through them below, because they show the point of the app better than the feature list. Setting up a council Creating a council is the whole setup: pick the deliberation mode, seat the models, choose who referees. The roster can mix providers freely — Anthropic, OpenAI, Google, Groq, OpenRouter, and local Ollama models can sit at the same table. Each seat shows its capabilities (vision, tools, reasoning) and context window at a glance, and each model's native abilities — web search, code execution, at
Apple’s trade secrets lawsuit against OpenAI contains allegations that range from employees joking about unauthorized access to Apple’s systems to claims that job candidates were asked to bring Apple hardware to interviews. Here are the complaint’s most eye-catching claims.
I released php-quic 1.0.0, a PHP extension that gives you raw QUIC transport with first-class access to streams. It links against the same OpenSSL that PHP already links against, and that is the whole trick. Why This Was Awkward Before QUIC is not a protocol you bolt on in userland. It is TLS 1.3, congestion control, loss recovery, and stream multiplexing, all riding on UDP, and all of it has to be right before you can send a single useful byte. You could get there from PHP if you were willing to bind to a foreign QUIC library like ngtcp2 or quiche through FFI. That works, but now your PHP app carries a second TLS stack, a second set of CVEs to track, a build story that involves Rust, and a version matrix that has nothing to do with the one your distro maintains. For a language whose entire deployment story is "the package manager handles it," that is a lot of rope. What Changed OpenSSL 3.5 shipped a native QUIC stack. Client and server, in the library PHP is already built against. That reframes the problem. The extension is no longer "embed a QUIC implementation into PHP." It is "expose the QUIC that is already sitting there." No new TLS stack, no FFI layer, no Rust toolchain in your build. If your OpenSSL is patched, your QUIC is patched. The requirements fall out of that directly: PHP 8.4 or newer (8.5 on Windows), NTS or ZTS OpenSSL 3.5.0 or newer, built with QUIC support Transport, Not HTTP/3 The thing I most wanted to avoid was shipping an HTTP/3 client and calling it a QUIC library. QUIC is a transport. HTTP/3 is one protocol that runs on it, and it is not the interesting one for everybody. DNS-over-QUIC runs on it. So does anything you want to invent that needs multiplexed, ordered, loss-recovered streams without head-of-line blocking across them. So php-quic hands you connections and streams, and stays out of the framing business. If you want HTTP/3, you build HEADERS frames and QPACK on top of it, and the README has a worked example. If you want something
🎧 DJ ROOTS – Building a Real-Time Collaborative Music Platform with Gesture Control Crowd Vibes. You Control. Music is one of the best ways to bring people together. However, during parties, college events, hostel gatherings, or study sessions, one common problem always exists— who gets to control the music? Usually, one person owns the playlist while everyone else keeps requesting songs. This often creates confusion, interruptions, and arguments over what should play next. Our team wanted to solve this problem by creating a platform where everyone in the room gets an equal voice. Welcome to DJ ROOTS . 🚨 The Problem Traditional music streaming at group events has several limitations: Only one person controls the playlist. Song requests are ignored or forgotten. No real-time collaboration. Existing queue systems don't truly represent the crowd's choice. There is no simple browser-based solution that works instantly without downloading an app. We wanted to build something that makes music democratic . 💡 Our Solution DJ ROOTS is a real-time collaborative DJ platform where anyone can join a room using a simple room code. Participants can: Create or join a music room Add songs using YouTube Upvote or downvote tracks Automatically reorder the queue based on crowd votes Watch every change happen instantly across all connected devices Let the host control playback using webcam hand gestures Instead of one person deciding the playlist, the entire crowd decides what plays next. 🛠 Tech Stack Frontend React 19 Vite Tailwind CSS v4 Framer Motion Three.js GSAP OGL Backend Node.js Express.js Database & Authentication Supabase PostgreSQL Supabase Authentication Supabase Realtime Computer Vision Google MediaPipe Gesture Recognizer Audio Pipeline yt-dlp youtube-dl-exec HTML5 Audio API Web Audio API Deployment Vercel (Frontend) ⚙️ How It Works Users create or join a room using a unique room code. Songs are added using a YouTube link or search. Song metadata is automatically fetched. E
Chipset makers and router manufacturers are talking about Wi-Fi 8, but what is the new standard, and when will it arrive?
This story originally appeared in The Algorithm, our weekly newsletter on AI. To get stories like this in your inbox first, sign up here. Anthropic—currently the world’s most valuable AI company, with a nearly $1 trillion valuation—has a reputation for publishing strange and heady research. It’s looking into whether AI models can feel pain, for example,…
Responding to Musk accusing him of being a scammer, Altman said, "homeboy you're the one sellling [sic] public market investors on short-term space datacenters."
The biggest smartphone makers keep on trucking in the face of component shortages and economic uncertainty.
General Fusion started trading on the Nasdaq following a reverse merger that saw high redemptions.