TypeScript Coffee

TypeScript 7 Went Native: What Actually Changes And What Doesn't

Everyone's heard by now that TypeScript "went native." And I keep seeing the same wrong conclusion... Read More

How I Smashed a Bug in a Shared Authentication Library

This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry. This happened a... Read More

Why Does Every AI Agent Still Look Like `while (true) { ... }`?

Most agent runtimes share the same brittle skeleton. Here's what happens when you replace it with an event log. Read More

Learn Valid Parentheses, Reverse Linked List, and Tree Max Depth with Step-by-Step Visualization in DSA View View 👀👀

Hoi hoi! I’m @nyaomaru, a frontend engineer who struggles to make game sounds. 😿 Have you used DSA... Read More

is-kit Reached 50 Stars ⭐ Here’s How We Use It in Production

Hoi hoi! I'm @nyaomaru, a frontend engineer who is trying to lose weight. 🐖🙀 I maintain a type... Read More

Stale infrastructure context is worse than none

The bug that isn't a bug On Tuesday you attach a dead-letter queue to orders-queue. On... Read More

Restate's Single Binary vs Temporal's Cluster: When the Lighter Engine Wins

Here is a bet that will save you a lot of arguing: pick your durable execution engine on what you... Read More

Fixing Exact Package Search Relevance in npmx

This is a submission for DEV's Summer Bug Smash: Clear the Lineup powered by Sentry. ... Read More

Is Learning DSA Boring? Let's Use DSA View View 👀👀 (Two Sum, Binary Search, and Bubble Sort)

Hoi hoi! I’m @nyaomaru, a frontend engineer who dislikes crowded places, so I'm planning to take a... Read More

Fixing a Silent Cache Bug in npmx.dev

This is a submission for DEV's Summer Bug Smash: Clear the Lineup. The bug npmx.dev is a... Read More

How I Stopped 429 Retries from Duplicating Successful Batch Jobs

This article is an English translation of the original Japanese article. This is a submission for... Read More

Nine green tests and a parser that never worked once

This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry. Two bugs, one... Read More

The bug that differential fuzzing cannot find

I ported a cron parser from TypeScript to Go and ran 36,000 differential test cases with zero divergence. Then I found a bug that no amount of fuzzing could ever have caught — because the output isn't a function of the input. Read More

linkedSignal() Writes Back: A Trace Through the Reactive Graph 🔍🚀

Let's be honest: linkedSignal() always had a bit of a split personality. It read beautifully from... Read More

I’m Looking for the Right Problem, Not the Right Job Title — Could It Be You?

This is a slightly unusual post. After almost 20 years of writing software, creating and leading an... Read More

Your birth time is lying to you: a time-zone rabbit hole in a Chinese astrology calculator

I built a calculator for BaZi — Chinese "Four Pillars" birth charts. Whatever you think of the... Read More

My Self-Evolving AI Agent Kept Passing Its Own Tests. The Code Had Never Run

Post #1 covered the birth. Post #2 covered pruning. Post #3 covered cost awareness. Post #4 covered... Read More

Build a Mini Engineering Graph With TypeScript and GitHub

You inherit a codebase. A file called checkout.ts is causing problems. You ask three... Read More

I Built a Password Strength Calculator That Never Sends Your Password Anywhere Here's the Entropy Math

Type Your Real Password Into a Random Website. What Could Go Wrong? Go search "password... Read More

I built an e-signature app that charges you for storage, not signatures

The bill that made no sense A signature is about 400 bytes of JSON and a hash. Every big... Read More

I Built a Lottery Simulator That Shows You Losing Money for 1000 Years

What I built howtolosemoneyfast.com is a satirical lottery analysis tool. You can simulate... Read More

Cheap Filters First, LLM Last: Running an AI Matcher Inside a Cron Job

I run a small SaaS called Upwork Scout. It watches Upwork around the clock and emails you only the... Read More

I failed a "design a document editor" interview, so I built one

Every resume builder is a form. Building the actual editor meant event sourcing, a page-break planner, and a PDF that matches the screen exactly. Read More

I type-check AI-generated SDK code against the real package. Claude refused a third of my Stripe tasks.

I build a small tool called SDKProof. It measures whether AI coding agents write a library's current... Read More