Chengjian Wu, Software Developer in Toronto, ON, Canada
Chengjian Wu

Software Developer in Toronto, ON, Canada

Member since June 21, 2016
Chengjian is a Ruby on Rails and React expert specializing in full-stack development. He has experience in a wide range of software development, including developing hybrid mobile social media apps, designing architectures, and building financial data processing systems. Chengjian can easily switch roles to collaborate with different teams to ensure that a project has an efficient and meaningful commit history for easy future maintenance.
Chengjian is now available for hire




Toronto, ON, Canada



Preferred Environment

Windows/Linux, Sublime Text, Slack

The most amazing...

...thing I've built was a stock order execution program in Python that reduces the slippage cost of stock purchases by more than 50% for Avaleren’s trading system.


  • React Native Engineer

    2019 - PRESENT
    Client (via Toptal)
    • Set up the project architecture, code standards, and linting rules for the React Native team.
    • Bridged third-party native modules for a React Native application.
    • Improved code clarity by chaining Redux actions using Redux-Saga and generator functions.
    • Reduced loading times of key screens by more than half through consolidating multiple API requests, in collaboration with the API team.
    Technologies: React Native, TypeScript
  • Founder

    2019 - PRESENT
    Wuinm, Inc.
    • Provided software consulting services.
    Technologies: Ruby on Rails, React, Node.js, SQL
  • Developer

    2017 - 2019
    • Created and maintained Avalaren's responsive official website using React:
    • Added a dynamic chart on the homepage comparing the portfolio performance against the benchmark index.
    • Performed daily financial data maintenance and data cleaning automation using Python/Pandas.
    • Built and maintained the data-quality wiki page to optimize research efficiency for team collaboration.
    • Constructed a hedged passive stock trading system using Python.
    Technologies: React, Redux, Redux-saga, Webpack, Axios, Material-UI, HTML, CSS, Python/Pandas
  • Quantitative Analysist

    2016 - 2017
    Blue Stone Invest
    • Cleaned, processed, and analyzed commodity futures historical market data using Pandas.
    • Researched and developed CTA trading strategies for Chinese futures markets using processed historical data.
    • Wrote evaluation reports of analysis of different trading strategies.
    Technologies: R, Python
  • Software Engineer

    2016 - 2016
    • Turned a Zeplin UI design into React components in collaboration with the UX team.
    • Worked as part of the front-end team and implemented MobX observables and actions and React Native pages.
    • Participated in code reviews and refactored the codebase.
    Technologies: JavaScript, React Native


  • Scixiv (Development)

    Scixiv is a writing/blog platform.

    Work Done:
    • Built a RESTful API using Ruby on Rails following TDD principles.
    • Developed the front-end layout (HTML/CSS) according to Google Material Design specifications/
    • Utilized JWT for a secure and stateless authentication system.
    • Constructed a real-time instant notification feature using longlasting WebSocket connections.
    • Used Netlify for a continuous delivery (CD) approach.
    • Reduce the release process into a single git push by turning the backend program into microservices (Docker, Kubernetes).

  • Official Website of Avaleren (Development)

    I developed the responsive official website using React and Node.js with MongoDB. The homepage chart compares the portfolio performance against the benchmark index using the data sent from the back end. I paid particular attention to implement a beautiful web UI design.

  • Boost Clouds (Development)

    I developed a VPN service application with a payment integration. It has a React front-end page with a Laravel framework-based back end.

  • Lunchiz (Development)

    I created a demo application for rating restaurants using React and Ruby on Rails. The code repository is at my GitHub page.


  • Languages

    JavaScript, Ruby, Python 3, TypeScript
  • Frameworks

    Ruby on Rails (RoR), React Native, Redux, Django, Material-UI,, Jest
  • Libraries/APIs

    React, Pandas, Node.js, React Redux, MobX, Redux-saga
  • Platforms

    Ethereum, Docker, Blockchain
  • Storage

    MongoDB, PostgreSQL
  • Other

    Concurrent Computing, Data


  • Master's degree in Physics
    2012 - 2015
    The State University of New York at Stony Brook - Stony Brook, NY, USA
  • Bachelor's degree with honors in Math and Physics
    2008 - 2012
    University of Minnesota Twin Cities - Minneapolis, MN, USA

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