How I Added Unit Tests to a Next.js Project Using Vitest (and Why It Matters for Portfolio Projects)
I recently built a SQL and Python interview prep app using Next.js, TypeScript, Supabase, and Vercel, with ChatGPT and Claude Code for code assist. Th
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Apr 01, 2026
Building a Multi-Agent AI System: How We Made 20 Agents Work Together
What is an AI Workout App?
An AI workout app is a fitness application that uses artificial intelligence to create and adjust your training
typescript
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Apr 01, 2026
I studied Claude Code's leaked source and built a terminal UI toolkit from it
On March 31, 2026, Claude Code's full TypeScript source was accidentally exposed via npm source maps. Like many developers, I started reading through
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Apr 01, 2026
Stop Writing Zod Schemas by Hand: What I Learned After 40 API Endpoints
*
I have a confession to make.
I spent three hours debugging a Zod schema on a Friday night. Not because the validation was complex. Not because
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Apr 01, 2026
Introducing HCEL: The Most Fluent Way to Build AI Pipelines in TypeScript
In the rapidly evolving landscape of AI development, orchestration is everything. As developers move from simple LLM calls to complex, multi-step agen
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Apr 01, 2026
How I built a React portfolio template with a LIVE color picker (and why it's a game-changer
🎨 How I built a React portfolio template with a LIVE color picker (and why it's a game-changer)
The problem with most portfolio
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Apr 01, 2026
Building CLAWX: From Side Project to AI Agent Marketplace - The Honest Journey
Building CLAWX: From Side Project to AI Agent Marketplace - The Honest Journey
Honestly, when I first started building CLAWX, I thought it
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Apr 01, 2026
Claude Code's Source Code Exposed — Every System Explained From Scratch (512K Lines)
Anthropic's Claude Code source just leaked. All 512,000 lines of it.
If you've used Claude Code, you know it feels like magic — you type a message, i
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Apr 01, 2026
I Read All 520K Lines of Claude Code's Source — Here's the Architecture Behind It
Anthropic's Claude Code source code just leaked. 512,000 lines of TypeScript. 1,900 files. The production-grade AI coding assistant that developers ha
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Apr 01, 2026
How I Built a 55-Tool MCP Server That Runs an Entire Business
Every ERP has a REST API. Ours has one too. But what made everything click was building an MCP server on top of it — 55 tools that let any AI agent ma
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Apr 01, 2026
The Illusion of Data Custody in Legal AI — and the Architecture I Built to Replace It
**There is a moment every legal AI founder eventually has to confront.
You have built a capable system. The retrieval is good. The citations hold up.
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Apr 01, 2026
I replaced 4 Play Console tabs with one terminal command
I used to start every morning the same way.
Open the Play Console. Check the releases tab. Switch to the vitals tab. Look at crash rates. Look at ANR
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Apr 01, 2026
Why TypeScript is Taking Over the JavaScript World
It's no secret that JavaScript has been the backbone of web development for years, yet an increasing number of developers are singing the praises of T
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Apr 01, 2026
Adding human approval to LangChain tool calls in 12 lines of TypeScript
Last week we needed to add approval gates to a LangChain agent that sends customer emails. The agent worked fine. The problem was it worked too fine,
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Apr 01, 2026
How I built MCP Apps based Sales Analytics Agentic UI & deployed it on Amazon Bedrock AgentCore
TL;DR: Learn how to add interactive forms, charts, visualization & PDF viewer - natively in your AI Agent chat window using MCP Apps.
AI Agents are g
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Apr 01, 2026
Quickly detecting JSON Escapes with SWAR
Most JSON string data is boring.
It is just ASCII text that does not contain " or \, does not dip below 0x20, and does not force any special-case esc
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Apr 01, 2026
Building a Multi-Tenant SaaS with Stripe Connect in 2026
If your SaaS handles payments on behalf of users (marketplace, platform, agency tool), you need Stripe Connect. Here's the architecture that actually
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Apr 01, 2026
ReactJS SOLID Principle ~ DIP (Dependency Inversion Principle)~
・The dependency that imports an extra module should depend on the abstract interface, but not the concrete one.
Because this makes it easy to modify
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Mar 31, 2026
How prefix-sum binary search makes text line-breaking O(log n) with zero allocation
Most text layout implementations find line breaks by scanning forward character by character, accumulating widths until they exceed the container. Tha
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Mar 31, 2026
Building Secure Session Management in NestJS - Refresh Tokens, Device Tracking & Session Revocation(PART 2)
1. The Refresh Token Flow — Validating Against the DB
This is where the real security upgrade happens. Instead of just verifying the JWT
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Mar 31, 2026