Your API provider shipped a breaking change. Here's how to find what it breaks in your code
When Dependabot bumps a dependency, the PR is green, the tests pass, and you merge it on autopilot. Three days later something in production throws a …
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qm multiplayer AI agent tutorial: Cut Latency 20% with Node.js
This article was originally published on BuildZn . Everyone talks about multi-agent systems but few show you how to actually coordinate them without a…
I Chased uWebSockets—and Found a 14-Byte Performance Cliff
Building ramjet-ws-js: a Rust-backed WebSocket path for Node.js that wins where it matters, admits where it loses, and survived 584 million verified r…
🚀 Building an AI Automation System for MyZubster
🚀 Building an AI Automation System for MyZubster Introduction MyZubster is an open-source ecosystem for plant mapping, privacy-first payments with Mon…
How to pick object storage for browser direct uploads with presigned URLs in Node.js
If you just want the recommendation: have your Node.js API mint a short-lived presigned URL, let the browser send the file straight into a private buc…
I tried to compile TypeScript into a native binary with scriptc
TL;DR: I tried to compile the TypeScript 6 compiler into a native binary with scriptc , and I failed — it got 90% of the way there and then hit an int…
Dockerfiles: Building and Running a Node.js Application in a Container
Introduction Containers provide a consistent way to package applications together with the dependencies and configuration required to run them. A Dock…
How redis-packhash Helps You Leverage Listpack Hashes in Redis
In my earlier post , I showed that storing a million small values as Redis keys is a waste of memory. It's because every key has its own overhead. To …
JWT Authentication in Node.js - A Complete Beginner Guide With Code
When I first tried to understand JWT authentication, every article I found either assumed I already knew what a token was or buried the actual impleme…
How I Built a CLI That Generates 12 Project Templates in 30 Seconds
How I Built a CLI That Generates 12 Project Templates in 30 Seconds When I started building ScaffoldX , I had a simple goal: create a CLI tool that ge…
Elixir vs Node.js: Why Developers Are Exploring Elixir for Modern Backend Systems
Modern backend development has been dominated by JavaScript runtimes like Node.js for many years. Node.js changed the way developers build web applica…
The Most Useful Support Agent Is the One That Cannot Send
An AI support demo can look complete after one successful exchange: a message arrives, the model chooses a tool, and a polished answer appears. The un…
From JavaScript to Node.js: Understanding What Really Happens Behind the Scenes (Part 4.1)
Node.js Modules Explained from Scratch — Why Do Modules Even Exist? If you've been writing Node.js for even a few days, you've probably seen code like…
Feature Flags and Safe Rollouts
In Audit Logs You Can Trust , we built a system that answers "who changed what, and when." Feature flags answer a related question: "who gets to see t…
Caching Strategies for a SaaS
In Disaster Recovery and Backups , we made peace with the database disappearing entirely: accept it can happen, and make recovery boring and rehearsed…
The Bug Only Happened After I Switched LLM Providers
The request succeeded. The response was valid JSON. The SDK did not throw an exception. And the application still broke. The bug appeared after I swit…
s3fifo 1.0: Zero-Allocation S3-FIFO Cache for Node.js is Ready for Production
Disclaimer: As a non-native English speaker, I used AI to help structure and polish this article. A few dayss ago, I shared Implementing a Zero-Alloca…
Your API Retried the Request. Your Customer Got Charged Twice.
A customer clicks the Pay button, the server sends the request to a payment provider, and the charge succeeds. The trouble begins when the response ne…
How to Use Bun 1.3.14's Built‑in Image API
I was scrolling through the Bun blog this morning and saw the announcement for Bun v1.3.14 . For a developer who spends a lot of time juggling Node, D…
Feature Flags Without LaunchDarkly: A 100-Line Solution
You want to merge a half-finished checkout redesign into main without breaking checkout for everyone. You want to ship a risky billing change but keep…
Writing TUI in the Terminal with Angular: Introducing @cyia/opentui-angular
Foreword Terminal applications (TUI, Text User Interface) have always had a unique charm — lightweight, fast, and cross-platform. From htop to vim , f…
How to Test SendGrid Webhooks Locally
The Challenge of Testing SendGrid Webhooks Locally SendGrid webhooks are powerful—they let you track email opens, bounces, clicks, and delivery status…
How to Test Razorpay Webhooks Locally
The Challenge: Testing Razorpay Webhooks Without Public Infrastructure Testing Razorpay payment webhooks locally is frustrating. Razorpay's webhook sy…
🚀 Deploy a Full Stack React Application (Firebase + Render) — Complete Deployment Guide (2026)
Deploying your application is one of the most exciting parts of web development. After spending hours building features, authentication, payments, and…
I Built a Free API That Detects Phishing Sites Using AI Vision — And It Catches Prompt Injection Too
Most phishing detection APIs check URL reputation databases. The problem? Brand new phishing sites aren't in any database yet. And a growing new categ…
Inter-Rater Agreement and Cohen's Kappa: When Your Labels Are Opinions
Two radiologists read the same 100 screening mammograms, each marking every scan "clear" or "suspicious." They agree on 92 of them. Cohen's kappa scor…
Goodhart's Law in Benchmarking: When the Metric Becomes the Target
A benchmark score going up is not evidence that the thing it measures got better. In 2015, regulators found that roughly 11 million diesel cars were r…
I Maintain 23 Benchmark Suites Across My Own Packages. Only 1 of the Serverless Ones Has Real Numbers Yet.
Five days earlier, an audit of my own ESLint plugins found 140 files still calling context.getFilename() , getSourceCode() , and getCwd() — three APIs…
A cut list is not a cut plan: audit kerf and stock assignments with KerfPlan
A cut list says which pieces are needed. A cut plan adds another question: which stock item is supposed to supply each piece, under which kerf and tri…
A ZIP can be valid and still unpack badly on another platform: inspect paths with PathParcel
A ZIP archive can have a perfectly readable central directory and still contain paths that are awkward, destructive, or ambiguous on the machine that …