Xavier Fernandes, Software Developer in Oakland, CA, United States
Xavier Fernandes

Software Developer in Oakland, CA, United States

Member since January 24, 2019
Xavier's experience spans web-based applications, including front end, back end, and infrastructure. He has built web applications using Flask and Django, and managed their deployments on AWS and other Cloud platforms. He communicates exceptionally well and has worked in teams of all sizes.
Xavier is now available for hire


  • Carbon Lighthouse
    Python, Flask, Django, Gevent, TypeScript, React, AWS Lambda, AWS Batch...
  • Zymergen, Inc.
    Python, Django, Celery, AngularJS, MySQL, Neo4j, Java, AWS Lambda, AWS Batch...
  • Plethora
    Python, Cython, C, C++, C#, G-Code, Parasolid, ModuleWorks, JavaScript...


  • JavaScript, 7 years
  • Jinja, 7 years
  • Flask, 7 years
  • Django, 4 years
  • JavaScript 6, 3 years


Oakland, CA, United States



Preferred Environment

Linux (Ubuntu, Debian), Sublime Text

The most amazing...

...project that I've worked on was a distributed task system using Celery, to calculate DNA primer sequences for engineering specific mutations in an organism.


  • Senior Software Engineer

    2019 - PRESENT
    Carbon Lighthouse
    • Automated deployment of an AWS EMR HBase cluster.
    • Added UI enhancements by building new UI components in React.
    • Added new functionality to existing AWS Batch and Lambda jobs, and automated deployment of the Batch and Lambda code.
    • Utilized the Gevent library to speed up simultaneous non-blocking IO calls, and increase the response times of some API endpoints.
    • Participated in requirements gathering and the producing of design documentation.
    Technologies: Python, Flask, Django, Gevent, TypeScript, React, AWS Lambda, AWS Batch, AWS Cloudformation AWS EMR, PostgreSQL
  • Senior Software Engineer (Computational Biology)

    2017 - 2018
    Zymergen, Inc.
    • Built and maintained software tools to facilitate DNA assembly and quality control.
    • Worked on cross-functional infrastructure improvements targeting memory efficiency, maintainability, and confidentiality of DNA sequence data.
    • Designed and built a logging system to help troubleshoot in-production software issues.
    • Built and maintained parts of a distributed task system based on Celery.
    • Built a system to explore metabolic networks using the Neo4j graph database together with publicly available data.
    Technologies: Python, Django, Celery, AngularJS, MySQL, Neo4j, Java, AWS Lambda, AWS Batch, Docker
  • Computational Geometry Software Engineer and Toolpath Team Lead

    2016 - 2017
    • Developed software to manipulate CAD model geometry in the Siemens Parasolid library.
    • Worked on a Cython wrapper of the Parasolid library to allow Python code to call into Parasolid C functionality.
    • Devised a Cython wrapper for the ModuleWorks C++ library, to allow ModuleWorks functionality to be called from Python.
    • Maintained and debugged a distributed task management system that interfaced with Cloud infrastructure and physical CNC mills in a factory.
    • Implemented geometric reasoning strategies for fixing milling defects in manufactured parts.
    Technologies: Python, Cython, C, C++, C#, G-Code, Parasolid, ModuleWorks, JavaScript, Node.js, PostgreSQL
  • Software Engineer

    2015 - 2015
    Brightlink Technology, LLC.
    • Created an analytics platform using Flask and PostgreSQL.
    • Performed a step-by-step replacement of an existing UI, based on JQuery, with new UI components built using React.
    • Built a load testing framework using Gevent, to test the analytics system under simulated real world load.
    • Worked with a client remotely to build an API that the client could use to pull data out of the analytics system.
    • Traveled to support the client on-site, for a real-world deployment of the software, and real-time troubleshooting of issues.
    Technologies: Python, Flask, CherryPy, Gevent, Apache, PostgreSQL, JavaScript, React.js
  • CTO

    2013 - 2014
    Campus Bubble, LLC.
    • Ran the support of an existing web app based on Handlebars, NodeJS and MongoDB.
    • Moved the deployment of the app from Heroku to AWS, and managed the deployment using Ansible.
    • Architected a fresh redesign of the same web app using ReactJS on the front end, and Flask with PostgreSQL on the back end.
    • Dealt with scalability issues by using HAProxy for load balancing and Redis for caching.
    • Hired a distributed team of developers and oversaw growth of the customer base, while steadily adding features to the app.
    Technologies: Python, JavaScript, Flask, Node.js, ReactJS, PostgreSQL, MongoDB



  • Languages

    Python, JavaScript, JavaScript 6, C
  • Frameworks

    Flask, Jinja, Django, Express.js
  • Libraries/APIs

    SQLAlchemy, React, Node.js
  • Tools

    Nginx, Ansible, Apache, AWS CloudFormation, AWS CloudWatch, MATLAB, Mathematica
  • Paradigms

  • Platforms

    Linux, Ubuntu 16.04, Docker, AWS EC2
  • Storage

    PostgreSQL, MySQL, MongoDB, NoSQL, AWS S3


  • Ph. D. in Mathematics
    2006 - 2012
    Emory University - Atlanta, Georgia, USA
  • Master's degree of Science in Mathematics
    2003 - 2005
    McMaster University - Hamilton, Ontario, Canada
  • Bachelor's degree in Mathematics
    2001 - 2003
    Virginia Tech - Blacksburg, Virginia, USA

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