Paulus Esterhazy pesterhazy

TL;DR: what's a good folder structure to use for a Typescript backend app?

Working on a larger monolithic app, I'm curious about best practices on structuring the project:

What should the folder hierarchy look like in 2025?
What are the abstractions or categories? (services, handlers, models, ...)
What dependency rules (optionally be enforced by dependency-cruiser) should be adopted? E.g. "api/*.ts can refer to db/*ts, but not vice versa"

What problems am I trying to solve?

All keybindings for macOS

Getting around

Select successively larger and larger sections (word, block, function), expanding upward and outward (Ctrl Shift Right)
Go back to the file and position where you last edited (Go to Last Edit Location): (Cmd R Cmd Q)
Go to last file: Cmd P P (keep Cmd pressed down)

Cursor's AI features

Websocket Deployments — Enemy of the State

How do you deploy new code continuously into a system that needs to support stateful, uninterruptible computations?

Some workloads are inherently stateful

As web developers, we're used to valuing stateless computation, for good reason – reducing state makes everything easier. Servers (or cloud instances) hold no essential state, delegating any important data to databases like Postgres and Redis. This is a great architecture. Among other benefits, it makes zero-downtime deployments a breeze: to deploy a new code version, you simply spin up a set of new instances with the new git sha, add them to the load balancer, and kill the old instances after draining them of traffic (perhaps after 60 s).

However, some workloads don't fit this "short-duration request & response" mold. As an example, consider connecting OpenAI Realtime to Twilio's API, which requires you to:

Why use classes in TypeScript?

There are many reasons why people like Object-Oriented Programming, but personally, my main reason for the use of classes in TypeScript is making dependencies explicit and replaceable. For example, suppose you have a module, Calendar, which depends on another module, GCalClient - i.e. Calendar uses the functionality from GCalClient but not vice versa. The most straightforward way to write that code is by simply using the functionality from GCalClient when needed:

// calendar.ts

import {bookAppointment} from "google-calendar-client"

function createMeeting() {

Dave Karow on Progressive Delivery - 4-part series

Behavioral questions (aka "Tell me about a time when...")

Tips for Tackling "Tell Me About a Time When" Interview Questions Like a Pro

Prepare a set of ~10 anecodotes from your previous experience and put them in 3 different buckets: Highlights, Working with others, and Tough times.
The Amazon Leadership Principles - A Complete Interview Guide

While this detailed post is about the Amazon's so-called Leadership Principles, the general approach can be used when interviewing for any company in talking about your experience.

This guide helps me set up my macOS laptop in a fairly simple manner. I'll need to go back to this guide roughly every 2–3 years. Maybe it'll help you, too!

Smart Caps Lock

Use Karabiner Elements

Map Caps Lock to Ctrl (when long-pressed) or Escape (when tapped). See this guide

Put backtick/tilde character to the left of 1 key

	# I never, ever want to open any files in Apple Music

	% osascript -e 'id of app "Audacity"'
	org.audacityteam.audacity

	% duti -s org.audacityteam.audacity public.mp3 all

	/**
	* Returns a normalized weekday int from 0..6
	*
	* Sun=0, Mon=1, Tue=2, Wed=3, Thu=4, Fri=5, Sat=6
	*
	* This has caused a number of bugs so an explanation is in
	* order. Javascripts's Date#getDay() methods returns a value from
	* Sun=0...Sat=6. In other words, the week starts on Sunday. However,
	* the ISO 8601 week starts on Monday, so the int values range from
	* Mon=1...Sun=7. The numeric values for Mon...Sat are the same, but

	async function bar() {
	throw new Error("boom");
	}

	async function foo() {
	return await bar();
	// same stacktrace printed with return bar();
	}

	function test() {