Jamie Wong



github.com/jlfwong	www.jamie-wong.com	jamie.lf.wong@gmail.com

Hi! I want to pursue challenges that require a more mathematical or scientific background than my past full-stack web development endeavours might suggest. I'd like reading papers or textbooks to be a part of my job, and for that reading to be necessary to do my job well. I'm an advocate of extensive automated testing (untested code is unmaintainable code) and code review (unreviewed code is incomprehensible code). I've started and contributed to popular open source projects here and there, and written about my work on both company engineering blogs and my own personal blog.

Select Projects and Blog Posts in Graphics

Real-time Fluid Simulation, August 2016

GPU implementation of a real-time interactive fluid simulation in WebGL
Accompanying blog post explores concepts of advection, divergence of the velocity field, and derivation and solution for a large system of linear equations yielding the pressure field

Ray Marching and Signed Distance Functions, July 2016

An overview of the ray marching algorithm, signed distance functions, calculation of normals for lighting, and modeling using constructive solid geometry
Demos powered by clearly commented GLSL code on Shadertoy

Work Experience

Software Developer in Infrastructure at Khan Academy, June 2014 - March 2016

Member of team of 4 engineers optimizing user-perceived site performance (4 months)
- Reduced time to visually complete for all critical content pages by > 50%
- Video page visually complete time reduced to 3s from 7s on a US DSL connection
- Focused on optimizations that applied well to India and other countries with similarly low bandwidth conditions
- Designed, co-authored implementation, and deployed server-side rendering service handling ~100QPS at peak traffic
Led engineering team of 4 to construct and launch translator portal (3 months)
- Used by teams around the world to monitor translation progress and stay focused on the most critical translation tasks, later leveraged to launch Khan Academy in Hindi
- Acted as primary contact with third-party service Crowdin's CEO and technical staff to secure bug fixes and feature development on their side necessary for our project's success
Worked with one other engineer to fix category of data loss caused by incorrect transaction usage (6 weeks)
- Built a distributed locking mechanism to prevent lost datastore writes (see blog post)
- Monkey-patched Google AppEngine datastore libraries to provide runtime assertions of transactional safety (see blog post)
Mentored intern for 4 months, helping her reduce the duration of deploys
Interviewed ~20 candidates for devops and software engineering positions

Software Developer Intern and Backpacker at Khan Academy, September - December 2013 (Remote)

Introduced a custom CommonJS-esque module system now deployed throughout the entire website
Built clientside JavaScript test infrastructure integratable into CI based on Mocha
Visited ~14 countries, mostly in Western Europe, working out of hostels and cafes

Security Engineer Intern at Square, January - April 2013

Worked on Keywhiz, a file-based secret management and distribution system (written in Java) deployed on all Square servers
Deployed applications into high availability environments with HAproxy
Created dashboard to track expiration of critical SSL certificates, likely preventing a few payment-blocking outages

Software Developer Intern at Khan Academy, May - August 2012 (Remote)

Worked with John Resig to build and launch the Khan Academy Computer Science platform, used by more than 100,000 users
Had full ownership over building the Google App Engine backend, contributed to in-browser programming environment

Frontend Developer Intern at Facebook, September - December 2011

Worked on early prototypes of Facebook Home, devtools, JavaScript test infrastructure

Sample of Open Source Contributions

Khan/aphrodite (co-author)

A performance-focused tool for writing CSS in JavaScript, built for React (see blog post)
> 300 downloads a day via npm, > 1000 stars on GitHub

jlfwong/chrome2calltree (author)

Converts CPU profiles exported from Chrome to callgrind format
> 300 stars on GitHub

mozilla/source-map (contributor)

Contributed patch for consuming indexed source maps for source-to-source debugging as part of work for Khan Academy
+1KLOC, -400LOC change to unfamiliar codebase

Other Technical Experience

jamie-wong.com - Personal Technical Blog

Over 150,000 unique visitors
Highest traffic post, "The Grep Test", received > 30,000 visits over two days

Competitive Algorithmic Programmer

ACM ICPC competitor, 13th place finish out of 113 teams in East Central North America
Facebook Hacker Cup Online Round 2 Qualifier, 2011, 2013
Google Code Jam Online Round 2 Qualifier, 2009, 2010, 2012, 2013, 2016
National Bronze Medallist, Canadian Computing Contest, University of Waterloo, February 2009

Stack Overflow Contributor

stackoverflow.com (username: Jamie Wong), March 29, 2010 - Present

Over 12,000 reputation, 240 answers

Languages

Extensive experience in Python, JavaScript
Working knowledge of Scala, Ruby, Java, C++, C
Reluctant knowledge of VimL and php
Would love to develop knowledge in Rust, Go, or OCaml

Education

Bachelor of Software Engineering, Co-operative Program, Dean's Honours List

Honours Software Engineering, University of Waterloo, Ontario, September 2009 - June 2014
Major Average: 94%

Interesting Coursework

Built a raytracer in C++, implementing vertex normal interpolation, Fresnel reflection, refraction, texture mapping, and depth-of-field for CS488
Wrote an operating system in C to run on an ARM processor, including a basic memory allocator, a co-operative scheduler, and interrupt handlers for SE350
Wrote a compiler in Scala targeting x86 for a large subset of Java, including a DFA-driven lexer, SLR parser, type checking, and code generation for CS444