daniel cho

A LETTER BY DANIEL CHO

A new letter every time I ship something: an app, a guide, a kit

Ship more with

Every letter is one ship: a thing I built on the side, how I built it, and what it changed.

Daniel Cho

Daniel Cho

Security engineer building apps, certs and income in public

@bydanielcho

01 /WHERE THE LETTERS COME FROM

Three places I ship from.

Hands on a laptop keyboard, code on the screen.

INSIDE THE BUILDS

Results from my apps

iOS apps, agent kits and the tools behind them, built at night with Claude Code. Every letter starts with something that actually shipped.

Daniel at a laptop by a high-rise window.

INSIDE THE CERTS

Results from my exams

15+ certifications, CISSP, CISA, Security+ and AWS among them, turned into study guides. What worked on the exam, not what the textbook says.

An indoor pickleball court mid-game.

OUTSIDE THE WORK

Results in my life

Marathon training, pickleball, the house, and what all of it costs. The numbers I would want from someone a few steps ahead.

02 /WHAT YOU GET

One ship per letter. Two minutes to read.

  • What I shipped, and why that one
  • How I built it, the tools and the steps
  • What it changed, and what it cost to get there

One ship at a time.

Free, whenever I ship, from someone building it on the side.

Send me the letters