A wide view of a green grassy valley with winding paths, a mountain on the right and the sun shining as a bright star above its edge in a blue sky.

Ezra Wu

I write backend systems for a living. Outside work, I study light: with a camera, and with code.

Backend / Platform Engineer

Sun over a valley14mm · f/22 · 1/125

Building

The next stage of the black hole renderer

Thinking about

Letting an AI act only after a person says yes

~/photos

Photos

Mostly a 35mm prime and an ultra-wide, often with the aperture wide open. Many of them are people standing small in a big landscape.

Tall dry grass in the foreground leading up to a sunlit ridge, with a line of hill and a clear blue sky above. — A grassy ridge in the sun35mm · f/3.5 · 1/2500

A person with short dark hair and a fringe, in a white striped sweater, sitting against a pale concrete wall in warm sunlight and looking at the camera. — Warm light on a concrete wall35mm · f/1.8 · 1/1000

A brown and black dog wearing a green harness walks towards the camera on a dry grass path, with a tiny distant person and hills behind. — A dog coming up the path24mm · f/2.8 · 1/800

A person in a white striped sweater and dark trousers turns to look over their shoulder, standing between two grassy banks under a clear blue sky. — Looking back35mm · f/1.8 · 1/3200

Three tall maroon posts with yellow Chinese characters at their tops, seen from low down against a deep blue sky, with dry grass at the bottom. — Three posts against the sky14mm · f/7.1 · 1/500

A person in a long deep red robe seen from behind, standing on a green lawn with low hills and a fence in the distance under a pale blue sky. — A figure on the lawn24mm · f/20 · 1/25

NIKON Z 6 · 35mm f/1.8 · 14–24mm f/2.8

~/lab

Lab

Light a camera cannot catch, I work out with code. Light it did catch, I take apart into letters. Each experiment starts from a question.

A black half-oval shape at the centre, with a smooth bright blue-white band curving around it against a soft grey-brown background.

If gravity bends light, what does the picture look like?

Black hole renderer

A program that draws what the space around a black hole looks like. It works out the path of light rays from physics equations, so the glowing ring and the bent starlight come from calculation rather than from painting. The look is inspired by the film Interstellar.

Rust · offline rendererSource ↗

A tiny person with a backpack walking up a narrow dirt path that winds through dry grass, with a mountain and hills in the distance.

How few letters does it take to recognise someone?

mirror

The mirror draws your camera as letters, live, on your own device. It is waiting at the bottom of this page.

camera · stays on your deviceGo to the mirror ↓

light, worked out

Explosion effects studies

Studying how to make explosion effects look convincing

Open in the terminal →

light, written

Text 3D

A spinning model drawn in letters, with light and shadow. The pointer turns it.

Open in the terminal →

~/work

Work

By day I build backend systems: databases, background jobs, and the messages that pass between parts of a system. Here are the public projects and a few documents.

Code

Writing

An AI that has to ask permissionA personal AI that runs on my own computer and needs a person to approve changesthinking
How to prove a system is right, not just fastA checklist for deciding whether a change is safe to releasethinking
A business plan that shows its evidenceTurning a business idea into claims that can be testedthinking
A backpack that nudges you to sit up straightA wearable design proposal that is honest about what is not tested yetdesign

~/about

About

            ######***+
        ##%%%%%#####***++=
      #%%%%%%%%%%####***++=-
     %%%%%%%%%%%%%####***++=-
   #%%%%%%%%%%%%%%####***++==-:
  #%%%%%%%%%%%%%%%####***++==--:
 *#%%%%%%%%%%%%%%####****++==--:.
 ##%%%%%%%%%%%%%#####***+++==--:.
*##%%%%=  @  =######=  @  ===--:.
*###%%.  @@@  .####.  @@@  .---:.
*#######.....###::***.....==--::.
**#############*::**++++===--::..
+***########****::*++++===--::..
=+*************o++o++====--:::.
 =++*********++++++====---:::.
 -=++++++++++++++====----::..
  -===+++++========--==:::..
   :-================:::..
     :-----------::::...
      .:::::::::::....
         .........

There is no photo of me here. Move the pointer and it looks at you; type and it talks.

I photograph light, work it out with code, and take it apart into letters.

I am Ezra, a backend and platform engineer. I help teams that already have a working product with the parts nobody sees: the database, the background jobs, and the way different parts of a system pass messages to each other.

Outside work I take pictures, render light from physics, and turn photographs into text. Every picture on this site appears as letters first.

Camera: Nikon Z 6
Lenses: 35mm f/1.8, 14–24mm f/2.8
Code: C# / .NET, Rust, TypeScript, Go, PostgreSQL
Languages: 中文, English
Work with me: Reliability problems behind a product that already runs

~/mirror

The last photo is you

Every picture above was someone else's light. This one is yours: your camera, drawn as letters on your own device.

Prints

Press the shutter and the frame is printed here as text you can copy.

~/contact

Want to make something together, or just talk about light?

ezra40907@gmail.comGitHub ↗

No cookies, no trackers. Every picture appears as letters first.