TypeScript Coffee

Reviving a 12K+ Star Abandoned Library: toastr-next v3 🍞

This is a submission for the GitHub Finish-Up-A-Thon Challenge What I... Read More

You’re a Real TypeScript Developer Only If...

A few months ago, I published You're a Real JavaScript Developer Only If... It was just a post for... Read More

TanStack Start Is Kind of a Big Deal

Introduction People keep telling me TanStack Start is kind of a big deal, and I wanted to... Read More

Next.js 16 Broke My App in 4 Places and None of Them Threw an Error

The CI was green. Build passed. No TypeScript errors. No warnings. Everything looked clean. I... Read More

7 New JavaScript Features (And 2 I'm Still Waiting For)

Remember how I promised you (or rather myself) two weeks ago that from now on I'd only write light,... Read More

After 7 Next.js 16 Caching Bugs, I Stopped Guessing and Built a System

There's a specific feeling you get after your third production caching incident. It's not panic.... Read More

Why My Analytics Was Logging Every Page Visit Twice (And How I Fixed It)

I built a custom analytics system into my portfolio backend — a Django REST API that records page... Read More

Making my TypeScript types 15.7x faster

What slows large TypeScript types down, how to measure it with @ark/attest, and the one-field match that made my schema library 15.7x cheaper to type-check. Read More

The Hidden Machinery Behind Background Jobs

This will be a boring article today, but I wanted to write it after talking to a developer who... Read More

TypeScript Patterns for Environment Variables

Yesterday, as I was working on a CORS configuration, AI generated a block of code for me: const... Read More

Mastering the Latest TypeScript: What's New in 6.0 (and a Peek at 7)

TypeScript 6.0 has been out for a few months now, and it's a bit of an unusual release. It's the last... Read More

CHANGELOG.md is for Both Humans and AI Now, So Let’s Automate It

Hoi hoi! I’m @nyaomaru, a frontend engineer who recently discovered the deliciousness of a cheese... Read More

Build your first MCP server in TypeScript: the 2026 setup that takes 30 minutes.

Build your first MCP server in TypeScript: the 2026 setup that takes 30 minutes. I had... Read More

Building One Knowledge Graph Across 46 Repositories With Static Analysis (Part 1)

A static-analysis approach to unifying 46 repositories (37 air-closet-side + 9 mall-side) of legacy production code into one knowledge graph. Why simply 'letting AI read the code' isn't enough, why I had to chase down boundary nodes (API endpoints, DB tables, Event topics), how I dealt with framework and library diversity, and what 3 months of trial and error solved or didn't solve — looking back through actual git history. Read More

Conduit: The Gateway I Built to Forget About

Three microservices, two incompatible auth models, one public endpoint, and a Go gateway that turned... Read More

Every Alarm Is a Crime Scene: Meet Poirot, the Read-Only Incident Detective

What if the thing that gets paged at 2am wasn't a person, but a detective that investigates the... Read More

The Playwright Playbook — Part 3: Multi-User, Multi-Tab & Browser Context Testing

Test real-time collaboration, role-based permissions, and multi-tab flows in Playwright. Two users. One test. The scenarios most frameworks simply can't handle. Read More

I gave 8 AI agents an island and watched a society emerge — wars, gossip, grudges, and peace

Tiny Civilization: what happens when AI agents have to live together I grew up on Age of... Read More

The Playwright Playbook — Part 7: The CI/CD Setup Nobody Shows You

A production-ready Playwright CI/CD pipeline — GitHub Actions, test sharding across machines, browser matrix, Docker for consistent environments, Slack failure notifications, and published HTML reports. Read More

The Playwright Playbook — Bonus: Refactoring Schema Validation with Zod

A reader asked for it — here's the hand-rolled schema validator from Part 4, refactored with Zod. Better error messages, free type inference, way less boilerplate. Read More

The Playwright Playbook — Part 1: Stop Writing Playwright Tests Like a Beginner

7 beginner mistakes that are quietly destroying your Playwright test suite — and the professional TypeScript patterns that fix them. Real before/after code included. Read More

The Bug That Passes Every Toolchain Check: Circular Dependencies in JavaScript

Circular dependencies compile cleanly, pass tests, and ship to production. Here are the 3 patterns that create them, what Node.js, webpack, Rollup, and esbuild actually do with them, and how to stop them before they compound. Read More

I Built an AI Issue Triage Bot in 500 Lines of TypeScript — Here's How

Every open-source maintainer knows the feeling. You wake up, check your repo, and there are 12 new... Read More

Desconstruindo o Build: Como o Tree-Shaking realmente funciona (e por que o Bundle importa)

Fala, comunidade dev! 👋 No primeiro artigo da nossa série sobre a migração do YMS (do Angular 16... Read More