Darion Cassel, Software Developer in Pittsburgh, PA, United States
Darion Cassel

Software Developer in Pittsburgh, PA, United States

Member since January 8, 2016
Darion is a research scientist pursuing a PhD in computer engineering with a focus in security. He has published papers at top security conferences and has over four years of experience developing applications in JavaScript and Python. Darion has worked for organizations like Facebook, the Center for Open Science, NASA, Rackspace, CommVault, and Bristol-Myers Squibb, and has experience managing small and large teams.
Darion is now available for hire




Pittsburgh, PA, United States



Preferred Environment

Vim Text Editor, ITerm, Jupyter, Visual Studio Code, MacOS

The most amazing...

...project I've worked on was a hyper-local anonymous messaging platform that enables individuals in conferences to communicate hassle-free.


  • Software Engineering Intern

    2016 - 2016
    NASA Goddard Space Flight Center
    • Led the development of a multithreaded data processing and graphing architecture called StreamGrapher, built for capturing and monitoring spacecraft data streams.
    • Built StreamGrapher with a data flow architecture, multithreading, job queues, binary data packet processing from GMSEC and UDP, and a web-based graphical front-end.
    • Created a unit test generation tool that creates almost-complete unit tests.
    • Improved the performance with dedicated UI and background worker threads.
    Technologies: Qt, Octave, MATLAB, Python
  • Contractor

    2015 - 2015
    Lagestee-Mulder, Inc
    • Updated the Drupal website to show greater organization of employees.
    • Reworked the SQL database employee records to match a new schema.
    • Cleaned old database records.
    • Created new pages and views to improve the employee display.
    • Updated the navigation to improve user experience.
    Technologies: CSS, HTML, MySQL, Drupal, PHP
  • Software Development Intern

    2015 - 2015
    • Aided in the transition from webmail code to a microservices architecture.
    • Extended a Python password phone-recovery API to include a delete functionality.
    • Coded an MVC-based UI with PHP, HTML, and CSS.
    • Tested with API mocking and integration tests in a Vagrant environment.
    • Developed a new logging and monitoring solution for webmail events.
    • Coded a daemon in Python for sending Syslog events to Flume and Carbon.
    • Helped configure a Jenkins build server to build a Python package for CI/CD.
    • Wrote the Chef cookbook (in Ruby) to use JMXTrans and manage related CentOS administration.
    Technologies: CentOS, Flume, Carbon, Graphite, Ruby, Jenkins, Chef, Flask, Python, PHP
  • Software Development Intern

    2014 - 2014
    • Led the development of a cloud calendar application called liveCalendar for a Simpana Webconsole product.
    • Wrote natural, language-based event recognition.
    • Built an application that merges many calendar providers into one calendar and provides both smart event recognition and natural language parsing.
    • Helped set up and test the Meteor deployment and configured the Nginx balancing.
    • Coded the application using the Meteor JavaScript framework, Java, CSS, and HTML.
    Technologies: CSS, HTML, JavaScript, NGINX, Apache Tomcat, Node.js, MongoDB, Meteor


  • Developer's Guide to Improving Project Structure in Meteor Applications (Publication)
    Meteor is a framework for rapidly building real-time JavaScript web applications. It can be used to build complex applications with amazing ease. However, that can often result in adoption of bad development practices and poorly structured code. In this article, Toptal engineer Darion Cassel shares some simple ways to improve the structure of your next Meteor-based web application without resorting to complicated boilerplates and scaffolding tools.


  • Platforms

    Meteor, Parse, MacOS, Visual Studio Code, Drupal, Ubuntu, CentOS, Android, iOS
  • Languages

    JavaScript, Java, Python, HTML, CSS, Ruby, Octave, C++, C, Swift, PHP
  • Frameworks

    Flask, Qt, Knockout (Knockout.js), Mithril.js, Bootstrap, OAuth 2, Ember.js, Django
  • Libraries/APIs

    jQuery, jQuery UI, Twilio API, Node.js, Carbon, Facebook API
  • Tools

    Atom, Xcode, Sketch, Jupyter, ITerm, Vim Text Editor, Apache Tomcat, NGINX, Chef, Jenkins, Flume, MATLAB
  • Paradigms

    Agile Software Development, Scrum, Reactive Programming, Functional Programming
  • Storage

    MongoDB, PostgreSQL, MySQL
  • Other

    Graphite, Homebrew


  • PhD in Computer Engineering
    2017 - 2022
    Carnegie Mellon University - Pittsburgh, PA
  • Bachelor's Degree in Computer Science and Mathematics
    2014 - 2017
    University of Virginia - Virginia

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