TypeScript Coffee

Execution Trees, Not More Logs: A Better Debugging Model for AI Agents

A flat log can tell you that five things happened. It often cannot tell you which operation caused... 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

Dev log #19 WebRTC v2 flows, agentic orchestration, and a perfectly synced vault

This week was a high-output sprint across the stack—from low-level p2p networking in Python to... 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

Learn Number of Islands, Invert Binary Tree, and Course Schedule with Step-by-Step Visualization in DSA View View 👀👀

Hoi hoi! I’m @nyaomaru, a frontend engineer who is surprised by how cold it is in the Netherlands... 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

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

The board came back. The highlights lied.

I ship Codenames AI, a web game. Each game mode keeps its own save in localStorage. Reload the tab,... Read More

Delta encoding multiplayer game state

Old Light is a browser strategy game where a tab can stay open for days. The client holds a full copy... 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

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

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

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

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 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 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 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

I Chased a Data Bug for an Afternoon. It Was Never About the Data.

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

A calendar library returned the same answer for every year — and my tests agreed with it

I build a Korean saju (BaZi) service. The whole pitch is that the numbers are computed... Read More

Reliable Form Submissions: Dirty State, Fingerprints, and Idempotency

A disabled Submit button protects the UI. It does not protect the data. It is tempting to... Read More

I'm building Guren, a fullstack TypeScript framework for the AI-agent era

Guren is a fullstack TypeScript framework for Bun. I started it because I wanted Laravel's shape in... Read More

Someone forked my React component instead of opening an issue

I maintain a small comic and manga viewer component for React called react-comic-viewer. The other... Read More

The Vacuum Approaches — you are the dog

This is a submission for Weekend Challenge: Dog Days Edition The Vacuum Approaches is a tiny... Read More