Andrei Cioara, Python Developer in London, United Kingdom
Andrei Cioara

Python Developer in London, United Kingdom

Member since March 18, 2019
As an engineer, Andrei enjoys making software run as fast as the hardware allows. Holding a master of engineering degree from Imperial College London, Andrei excelled in his studies and graduated with a first class honors distinction. Andrei has previously worked at Microsoft, Palantir Technologies, Citadel Securities, and Jump Trading.
Andrei is now available for hire




London, United Kingdom



Preferred Environment

Amazon Web Services (AWS), AWS, Git, Bash, C++, Python, JavaScript

The most amazing... I've built is Officeroo, alumnus of YCombinator's Startup School and invited for interviews for the W19 batch.


  • Software Engineer

    2018 - 2018
    Citadel Securities
    • Developed custom Python and C++ software for the European Options Market Making desk.
    Technologies: Python, C++
  • Software Engineer

    2016 - 2018
    Jump Trading
    • Wrote fast-path C++ code for exchange connectivity and order placing.
    • Ported legacy C++ software to web technologies using React, D3.js, Django, and Tornado.
    • Developed a highly robust multithreaded PyQt application that runs on 400+ trader desktop machines.
    Technologies: Full-stack, Back-end, Front-end, D3.js, Redux, React, JavaScript, Python, C++
  • Software Development Engineering Intern

    2015 - 2015
    Palantir Technologies
    • Improved the JavaScript code performance by 400x (average) for one of our main users.
    • Contributed to the API design for the 1.0 release of PlottableJS (Palantir's largest open source project at the time).
    • Improved the tooling for the team and reduced build times by up to 30%.
    Technologies: D3.js, JavaScript, TypeScript
  • Freelance Web Developer

    2013 - 2015
    CoLake Care + PeopleGraph
    • Developed custom CSS pixel-perfect designs from Adobe Illustrator designs.
    • Implemented the full-stack of a Laravel (PHP) application, deployed it to production on AWS and used with trial patients.
    • Created a Google Chrome extension that improves the social network experience for recruiters.
    Technologies: Chrome Extensions, CSS, JavaScript, PHP
  • Software Development Engineering Intern

    2014 - 2014
    • Developed an iOS app for the customer relationship management team, Microsoft Dynamics.
    • Wrote a C# MVC application with a REST API which later served as a data source for the iOS app.
    • Researched the new capabilities of iOS 8 in anticipation for the September 2014 launch.
    Technologies: iOS, Objective-C, JavaScript, C#
  • Software Development Engineering Intern

    2013 - 2013
    • Developed Java code for the full-stack of
    • Wrote custom CSS rules that ensured cross-browser compatibility all the way to IE6.
    • Received a special end-of-internship bonus and return offer in recognition of my great work.
    Technologies: Java


  • Officeroo

    I was responsible for the product architecture, React-based front-end, Django back-end, AWS management, and more. I also managed sales and marketing; including the launch of our product with four beta clients and managing a team of three. We graduated from YCombinator’s Startup School and was invited to the YCombinator interviews, class of W19.

  • Cashflow

    This was a personal project for managing personal finances. The app also connects to external APIs for fetching market data. It was written using React, Redux, and Chart.js.

  • Palindrome

    Palindrome is a superior replacement for Mac's Finder or Window's Explorer. The features include the following: copy, move, delete, mkdir, mkfile, archive, extract, and synchronize.

    I developed this cross-platform two-pane file manager written in Electron.js; using React, Redux, Bootstrap, Redux-Thunk, and Electron.js.

  • Community Author

    I wrote five-star editorial articles for software interview questions. It received 50,000 to 100,000 views/article along with positive feedback. The written sample solutions are in Java.

  • Technology & Lifestyle Blog

    On this blog, I am the sole owner and editor. On average, I received 10,000+ views per article. My articles frequently trend on and; these articles have also been picked up by other syndication websites.

  • Personal Website

    It has the best SEO. This site was boosted to #1 on both Google and Bing for the keyword "Andrei Cioara" (It has since fallen to #2 as my own blog topped #1). I also designed the custom look and feel for both phone and laptop using plain CSS3 and HTML5.

  • Flappy Froggy

    I built this mobile game in Java and published it to the Google Play Store. I collaborated with a talented artist to create game graphics and written the entire physics engine from scratch. The game grossed about £10 with minimal promotion.


  • Languages

    Python, Python 3, Python 2, JavaScript, JavaScript 6, JavaScript 5, C++, C++11, Java, HTML, HTML5, CSS, CSS3, C, SQL, Java 6, Java 7, HTML4, Bash, Bash Script, TypeScript, C#, Objective-C, PHP, Haskell
  • Libraries/APIs

    jQuery, React, React Redux, Pure CSS, Node.js, Python API, JavaScript Charting, Django ORM, HTML5 APIs, Reactstrap, jQuery CDN, Stripe API, Plottable.js, D3.js, Redux Form, GitHub API, JavaScript API for Chrome, Moment.js, PyQt, PyQt 5
  • Tools

    GitHub Pages, JavaScript Debugging, JavaScript Toolchain, GitHub, Chrome Developer Tools, Webpack, Webpack 2, Webpack 4, Webpack 3, Git, Redux Thunk, Jenkins, Travis CI, CircleCI, GitLab, GitLab CI/CD
  • Platforms

    Google Chrome, Android, Linux, Amazon EC2, Firefox, Amazon Web Services (AWS), Windows, iOS
  • Storage

    JSON, MySQL, PostgreSQL, SQLite, AWS S3
  • Other

    Data Structures, Algorithms, Technology, HTML UI, CSS Grid, Bootstrap UI, Chrome Extensions, Finance, Sorting Algorithms, Writing & Editing, AWS, Front-end, Back-end, Full-stack, Tornado, Firefox Extensions, Entrepreneurship
  • Frameworks

    Django, React Native, Redux, Electron, Bootstrap, Bootstrap 3, Bootstrap 3+, Bootstrap 2, Laravel, Chrome, Express.js
  • Paradigms

    HTML DOM, Agile Software Development, Test-driven Development (TDD), Continuous Delivery (CD), Continuous Integration (CI)


  • Master's Degree in Software Engineering
    2015 - 2016
    Imperial College London - London, UK
  • Bachelor's Degree in Computing
    2012 - 2015
    Imperial College London - London, UK


  • Mensa Member (High IQ Society)
    JULY 2017 - PRESENT
    American Mensa

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