Joshua "Tsubaki" Wu

I'm a developer from the San Francisco Bay Area/Silicon Valley.・510-378-4220

I do.

  • Work

    • Facebook - Solutions Engineer

      Menlo Park, CA
      September 2016 - Present

      • Time split guiding clients to increase advertising revenue while coding new solutions.
      • Align interests with external advertising clients to build products addressing core issues.
      • Leverage Facebook data and technologies to propose new metric measurement solutions.
      • Built data pipeline to measure significant Facebook ads ROI on non-Facebook search traffic.
      • Built internal pipeline to measure and quantitatively demonstrate team effectiveness.
      • Work with product teams to build new products and improve existing ones.
    • Quixey - Software Engineering Intern

      Mountain View, CA
      May 2015 - August 2015

      • Developed a project progress tracker in Meteor for internal management across all teams.
      • Work with various teams on different projects, understanding and fixing their problems and often writing code for them on which they otherwise would have been stuck.
      • Code components involving NLP algorithms and APIs of partner companies.

    Personal Startup Projects

    • Impact - Natural Language Processing Framework

      Spring 2014 - Current

      • Evaluate natural language using highly efficient parser.
      • Machine learning on probabilistic context-free grammars.
      • Handle grammars of arbitrary size (> 100,000) and ambiguity. Parse time < 30 ms.
      • Query meta-language for defining grammars.
    • joseki farm

      Spring 2014 - Current

      • Both an engine and a web-based training game for go players built such that one very inexpensive web server machine can instantly perform transactions verifying the player’s solution.
      • Dedicated SGF converter and compression algorithms to fit millions of board positions on megabytes.
      • Backend verifies instantly the validity of move sequences sent by clients (difficult for users to cheat) through path existence and caching. Very efficient tracking of each user with every known board state using database joins.
      • I am building this with a partner. We have both worked on 100% of the code.
      • Built on Ruby on Rails. Integrated with AWS, PostgreSQL, Heroku, and mail servers.
      • Farm pineapples while learning joseki to get stronger at go. Become the master farmer and get lots of fruit.
    • Art Sharing Platform

      Username: janedoe
      Password: password

      Fall 2013 - Fall 2014

      • An art sharing platform with the focus on having better image processing techniques and networking environment compared to the other art platforms. In contrast with other websites such as DeviantArt (a competitor with slow legacy software and an unworkable interface, constantly criticized by its users), the application is built to be very scalable, fast, response, and intuitive for users. A fuzzy, live search omnibar allows users to instantly find their desired content.
      • Contains responsive, beautiful collage homepage layout made possible by powerful crop-sizing algorithms.
      • Images of all sizes and shapes can be uploaded, compression, and intelligently processed.
      • Fully-functional social networking features (albeit not publicly released yet).
      • I am currently the sole engineer. 100% of the website code is developed by me.
      • Built on Ruby on Rails. Integrated with AWS, PostgreSQL, Redis, Heroku, and mail servers (registration currently disabled).
    • Joysound Search

      search for Joysound's Chinese (or Japanese) karaoke songs using hanzi or pinyin (or plain Japanese)!

  • Other Projects

    • PintOS

      Fall 2014

      • Led a team of 4 to build a complete OS on top of a very basic PintOS framework.
      • We enabled multithreading, virtual memory, handled system calls, and a filesystem supporting syscalls and protected by locks.
      • We implemented various thread scheduling algorithms, including a priority scheduler that gives higher priority to important threads while ensuring no starvation can occur.
    • Key-Value Store

      Fall 2014

      • With a team of 4, I created a distributed master-slave key-value store capable of tolerating failures and ensuring consistency.
      • Implemented two-phase commit with transaction logging for reliability.
    • Fast Image Convolution

      Spring 2013

      • Led a team in implementing a fast image convolution algorithm.
      • Algorithm took into consideration of machine-level details such as doing smart cache blocking when performing matrix multiplication.
  • (other projects currently undisclosed)

I work with people.

Teacher/Mentor and Team Leader

2013 and 2014 GPIUS/ISA Japan Empowerment Programs
Summer 2013 and 2014
  • Created a website as a forum for the program participants.
  • Experienced working with Japanese colleagues and superiors, a foreign cultural setting
  • Raised confidence and self-esteem in Japanese high school students
  • Cultivated leadership and presentational skills to students
  • Inspired Japanese students to dream big and solve problems
  • Raised awareness of domestic and global issues
  • Taught English

IT Consultant and Webmaster

UC Berkeley Botanical Gardens, Berkeley, CA
February 2013 - July 2013
  • Fixed networking failures and advised administration
  • Implemented proper website practices, raising the website score from F to A
  • Fixed thousands of broken references on website and removed obsolete methods
  • Began migration to to Drupal

Former Club President at Mission San Jose HS

President of Japan Culture Club
2011 - 2012
  • Paneled "So You Wanna Learn Japanese?" at FanimeCon 2013
  • Increase membership from eight to eighty
  • Teach Japanese culture
  • Led on and off-campus club activities
President of Anime Club
2010 - 2012
  • Increase membership from 12 to 230
  • Led on and off-campus club activities
Vice President of Go Club
2011 - 2012
  • This is Go. (Then there's Go.)
  • I'm 3-dan in Go. (Like a third-stage black belt in karate.)
  • I often teach players on the Kiseido Go Server.
  • If you play, add TAPJoshua on KGS!

I hack.


  • C
  • C++
  • Java
  • Python
  • Javascript
  • Coffeescript
  • Ruby/Rails
  • Purescript
  • Elm
  • Clojure
  • Objective-C
  • English (mother tongue)
  • Japanese (fluent)
  • Chinese (fluent)
  • Korean & German (currently learning)

Miscellaneous Technologies

  • Meteor
  • PostgreSQL
  • MongoDB
  • RethinkDB
  • Redis
  • vim
  • git
  • mercurial
  • atom
  • sublime
  • AWS: EC2, S3, EB, SES
  • Facebook Graph API
  • Heroku

I love.

  • Anime
  • Boba
  • Karaoke
  • Violin
  • Drawing
  • Izakaya
  • Crepes
  • Dancing

I learn.

University of California, Berkeley

B.S. - Electrical Engineering and Computer Sciences (EECS), 2016

Relevant Courses

  • Structure and Interpretation of Computer Programs
  • Data Structures
  • Machine Language
  • Software Engineering
  • Algorithms
  • Operating Systems
  • Artificial Intelligence
  • Technology Entrepreneurship
  • Computability and Complexity
  • Circuits and Systems
  • Computer Security
  • Discrete Mathematics
  • Multivariable Calculus
  • Linear Algebra and Differential Equations
  • Heat, Electricity, Magnetism


  • The President of the United States Volunteer Service Award
  • Chinese American Semiconductor Professional Association (CASPA) Scholastic Achievement Award
  • National Merit Finalist
  • AP Scholar with Distinction
  • National Honor Society Member

High School

  • SAT: 2350/2400
  • SAT Physics
  • SAT Chemistry
  • SAT Japanese
  • SAT Mathematics II
  • AP Calculus BC
  • AP Physics B
  • AP Chemistry
  • AP Statistics
  • AP Psychology
  • AP Japanese
  • AP Chinese
  • AP Music Theory