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My "serverless" database was billing me like it never slept. Neon has this great feature called scale-to-zero. Your Postgres compute suspends when it's idle, so you only pay for the queries you actually run. For a pre-revenue product, that should cost a few cents a month. Mine ran 24/7. The compute never once scaled to zero. The culprit wasn't my app logic. It was my database driver. I was using postgres-js, which holds a persistent connection open to the database. From Neon's side, an open connection looks like activity, so it never suspended. It just stayed awake and kept quietly billing me. The fix was basically one conceptual change: switch to @neondatabase/serverless, the HTTP driver. Instead of a long-lived connection, every query becomes a stateless one-shot HTTP request. The query fires, the connection closes, and the compute is free to suspend. Scale-to-zero finally worked. The lesson I keep relearning as a solo founder: "serverless" is a property of your whole stack, not a checkbox on one service. One persistent connection upstream and the whole cost model breaks.

I needed to convert 500 product images from one format to another. Server-based solutions quoted $15-50/month for batch processing. So I built a client-side solution using Web Workers and OffscreenCanvas. The Architecture The key insight: Canvas operations on large images block the main thread. The fix: Web Workers handle image decoding/encoding off the main thread OffscreenCanvas renders without DOM access — perfect for worker contexts Transferable objects pass image data between workers with zero-copy const worker = new Worker ( ' processor.js ' ); const canvas = new OffscreenCanvas ( 800 , 600 ); // Worker processes image, main thread stays responsive Real Performance Processing 500 images (average 2MB each) on a mid-range laptop: Server upload approach: 12 minutes (mostly upload time) Browser-local with Workers: 3 minutes 40 seconds Memory usage: Stable at ~400MB with proper cleanup The Tools I packaged this into webp2png.io for batch WebP conversion and svg2png.org for vector batch processing. For barcode generation, genbarcode.org uses similar worker-based rendering for bulk label generation. If you're processing more than 50 images, Workers + OffscreenCanvas is the way to go. Your server bill will thank you.

I analyzed what happens when you upload a photo to 5 popular free image compression sites. The Test I uploaded a 4.2MB photo to each service and monitored network requests. Results: Service A : File sent to their CDN (AWS us-east-1). 12 analytics trackers fired simultaneously. Service B : File uploaded, but 5 minutes later a second request sent the file to a different domain. Service C : Cleanest of the five, but their privacy policy reserves the right to "use uploaded content to improve compression algorithms." Service D : 23 third-party scripts loaded on the page. Your image URL is accessible to all of them. Service E : Actually clean — only one request to their server for processing. Only one of five didn't leak data to third parties. One. The Alternative I built compress2png.com to test whether image compression could work without any server. Turns out Canvas API + clever JavaScript handles it: Resize images client-side before export Strip EXIF/metadata in the browser Convert to optimal formats based on content For format-specific needs, svg2png.org handles vector conversion and webp2png.io handles next-gen format conversion — all browser-local. Check the Network tab next time you use a "free" online tool. You might be surprised what you find.

I have been writing a lot about AI lately, but this one is more personal than usual. Not a tutorial,...

A personal AI agent that runs on your desktop and iPhone Discussion | Link

Hello Folks! Agentic Orchestrator is a terminal tool that takes complex feature requests and builds them by orchestrating coding agents through a series of phases that emulate a full-fledged engineering flow: requirements clarification, research, design, multi-phase planning, implementation, and review. It is a single pane of glass for all your features and exposes post-publish utilities such as resolving merge conflicts and responding to review comments. The key design choice is that this is de

AI เขียนโค้ดแทนเราได้แล้ว — แล้วเราจะเหลืออะไรให้ทำ? มีประโยคที่ได้ยินบ่อยขึ้นทุกวัน: "เดี๋ยวนี้ใครยังไม่ใช้ AI ช่วยเขียนโค้ดบ้าง?" คำตอบคือ — แทบไม่มีแล้วครับ ตั้งแต่ GitHub Copilot, Cursor, Claude, ChatGPT ไปจนถึง agent ที่เขียนโค้ดเองได้ทั้ง project — เราใช้ AI ใน level ที่ต่างกัน: Level หน้าตา ตัวอย่าง 🎵 Vibe Coding พิมพ์สิ่งที่อยากได้ กด accept อย่างเดียว "เขียนหน้า login ให้หน่อย" → กด tab tab tab 🧩 Prompt-Guided คิดก่อน ถามทีละส่วน ตรวจทุกอย่าง "สร้าง UserService ที่ใช้ bcrypt hash password" 🛠️ Skill/Lint-Guided ใช้ AI เป็น editor ชั้นสูง — lint, refactor, test "refactor function นี้ให้เป็น table-driven test" 🏗️ Agent-Based ให้ AI run ทั้ง project — spawn subagent, PR, deploy "พอร์ต microservice นี้จาก Express ไป Fastify" แล้วคำถามคือ — ถ้า AI ทำทั้งหมดนี้ได้ แล้วมนุษย์อย่างเราเหลืออะไร? Unit Test — ตัวอย่างที่เห็นชัดที่สุด ลองดู unit test ที่ AI เขียนให้: // 🤖 AI-generated test func TestCalculateDiscount ( t * testing . T ) { tests := [] struct { name string input float64 expected float64 }{ { "zero" , 0 , 0 }, { "normal" , 100 , 90 }, // 10% discount { "max" , 1000 , 800 }, // 20% discount } for _ , tt := range tests { t . Run ( tt . name , func ( t * testing . T ) { result := CalculateDiscount ( tt . input ) if result != tt . expected { t . Errorf ( "got %v, want %v" , result , tt . expected ) } }) } } ดูเผิน ๆ — สวย, table-driven, ถูกต้องตาม Go convention 1 แต่ถามหน่อย — test นี้บอกอะไรเกี่ยวกับ business? "ส่วนลด 10% สำหรับยอด 100 บาท" — ทำไมต้อง 100? เป็นกฎจากที่ไหน? "ส่วนลด 20% เมื่อยอดถึง 1000" — แล้วถ้าลูกค้าเป็น member ได้เพิ่มอีก 5% ล่ะ? input: 0, expected: 0 — test นี้ cover edge case หรือแค่ cover บรรทัด? AI test ได้ถูกต้องตาม function — แต่มัน ไม่รู้ว่า business จริง ๆ คืออะไร AI ไม่รู้ Business Context — และจะไม่มีวันรู้ นึกภาพระบบ e-commerce: ลูกค้าซื้อสินค้า → ระบบตัดสต็อก → คำนวณส่วนลด → คิดค่าส่ง → ออกใบเสร็จ AI แยก test ทีละ function ได้: ✅ TestDeductStock — "ตัดสต็อก 1 ชิ้น" ✅ TestCalculateDiscount — "ส่วนลด 10%" ✅ TestCalculateShipping —

I'm a solo founder building AMA2, a messaging runtime made for AI agents. This is my first Show HN, so I'd really appreciate your feedback. What brought me this idea: At first, I was building an AI agent for solo creators that knows everything about you and can do business chore on your behalf. When I tried to plug it into normal chat tools like Telegram, Discord, Slack... , they all felt wrong for agents: 1. They don't care about an agent's context. To follow a thread, the agent has to pull the

🚀 Build Your First Space Shooter Game with Limn Engine A Complete Step-by-Step Tutorial for JavaScript Beginners Welcome! In this tutorial, you'll build a complete space shooter game using Limn Engine — a zero‑configuration 2D game engine that runs in your browser. What you'll build: A spaceship that moves, shoots bullets, fights waves of enemies, and keeps score. All in about 100 lines of code . By the end, you'll understand: How to create a game loop How to handle keyboard input How to detect collisions How to use particles for visual effects How to manage game state (lives, score, game over) 🎮 Want to play the finished game? Click here to play Space Shooter Live! Before We Start What You Need A text editor (VS Code, Notepad, or any code editor) A web browser (Chrome, Firefox, Edge) Limn Engine — download epic.js from limn-engine-doc.vercel.app What You Should Know Basic JavaScript (variables, functions, arrays, if-statements) How to open an HTML file in a browser No game development experience required! Step 1: The HTML Structure Every Limn Engine game starts with a simple HTML file. <!doctype html> <html> <head> <script src= "asset/epic.js" ></script> </head> <body> <script> // All your game code goes here </script> </body> </html> What's happening: <script src="asset/epic.js"> — loads the Limn Engine library Everything inside the second <script> tag is your game code Save this as game.html and open it in your browser. You should see a blank canvas with a blue gradient background. Step 2: Setting Up the Game The first thing we need is a Display — this is the engine that creates the canvas, runs the game loop, and handles input. const display = new Display (); display . perform (); // Activates performance mode (dual-canvas rendering) display . start ( 800 , 600 ); // Creates an 800×600 canvas What's happening: new Display() — creates the engine display.perform() — turns on high-performance mode display.start(800, 600) — creates a canvas 800 pixels wide and 600 p

Most of us share files constantly: config files, API specs, design assets, build artifacts. And most of us don't think too hard about where they end up. That's exactly what Zero-Knowledge Architecture (ZKA) is designed to address. But the term gets thrown around loosely, so let's break down what it actually means — and what to look for. The Core Idea: The Server Shouldn't Have to Trust You Traditional cloud storage works roughly like this: You upload a file The server encrypts it (or doesn't) The server holds the key You trust them not to look Zero-knowledge flips this entirely. In a true ZKA system: Encryption happens on your device , before data leaves your control The keys never leave your side — the server never sees them The server handles only encrypted blobs — it's a pipe, not a vault The phrase you'll hear is: "We can't read your data even if we wanted to." That's the point. Why This Actually Matters Here's a concrete scenario: you're sharing a .env file with a contractor. You use a cloud service. The service gets breached a week later. With standard encryption (server holds the key): the attacker potentially has your secrets. With ZKA: the attacker has an encrypted blob that's useless without the key they never had. Beyond breach scenarios, ZKA also helps with: Regulatory compliance — GDPR, HIPAA, and similar frameworks become easier to demonstrate when the service provider has zero access to the data Reduced trust surface — you're not trusting the company, their employees, or anyone who might compel them legally What Real ZKA Looks Like in Practice There's a big difference between claiming zero-knowledge and actually implementing it. Here's what to look for: ✅ Client-side encryption Files should be encrypted in the browser or app before upload. Not on the server. If encryption happens server-side, it's not zero-knowledge — it's just encrypted storage. ✅ Key management stays with you Where do the keys come from? How are they shared with recipients? In a rea

Let’s be honest: as developers, our relationship with our office chairs is... complicated. We start the day sitting upright like productivity gurus, but four hours into a debugging session, we’ve morphed into a human pretzel. This "gamer lean" isn't just a meme; it leads to chronic back pain and decreased focus. In this tutorial, we are going to build a real-time posture tracking system using MediaPipe Pose and Computer Vision to save your spine. By leveraging AI productivity tools and the power of cross-platform Electron desktop apps , we will create a silent guardian that watches your form and pings you the moment you start slouching. If you've been looking for a practical way to dive into MediaPipe and Node.js integration, you're in the right place. For those looking for more production-ready patterns and advanced AI implementations, I highly recommend checking out the deep dives at WellAlly Blog . 🏗 The Architecture The system works by capturing frames from your webcam, processing them through a pre-trained neural network to identify body landmarks, and then applying some basic trigonometry to determine if your posture is healthy. graph TD A[Webcam Stream] --> B[MediaPipe Pose Engine] B --> C[Extract 33 Keypoints] C --> D{Geometry Engine} D -->|Angle > Threshold| E[Slouch Detected] D -->|Angle < Threshold| F[Good Posture] E --> G[Electron Main Process] G --> H[System Notification 🔔] F --> I[Wait 5s] I --> A 🛠 Prerequisites To follow along, you'll need: Node.js (v16+) MediaPipe (The pose solution) OpenCV.js (For frame manipulation) Electron (For the desktop shell) 🚀 Step 1: Setting Up the Pose Engine MediaPipe provides a "Pose" model that gives us 33 landmarks in 3D space. For posture correction, we specifically care about the Ears (7, 8) , Shoulders (11, 12) , and Hips (23, 24) . The Math: Calculating the "Slouch" We measure the angle between the Ear, the Shoulder, and a vertical axis. If your ear moves too far forward relative to your shoulder, that's "Forward