Eddie Sullivan, Developer in Charleston, SC, United States
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Eddie Sullivan

Verified Expert  in Engineering

Mobile App Developer

Charleston, SC, United States
Toptal Member Since
April 10, 2018

Eddie is dedicated to exceeding your expectations with the highest-quality mobile and web software, delivered on time and to your precise needs. High-profile clients have included the US government and Rexel. His qualifications include two decades of industry experience with a passion for continued innovation using the latest technologies. Eddie joined Toptal because he wanted to work on a freelancing platform, and Toptal stood out from the rest.


Seashore Software
Android, iOS, Django, Java, C++, Objective-C, Swift, Python, React...
Gemstar | TV Guide Onscreen
C#.NET, .NET, Firmware, Python, C#, C, Unit Testing, REST APIs
Juniper Networks (formerly Unisphere)
Firmware, Networking, VxWorks, C++, C, Unit Testing




Preferred Environment

Linux, Windows, MacOS

The most amazing...

...experiences have been the ones in which I used my skills to create something new, beautiful, and useful.

Work Experience

Founder | Software Engineer

2006 - PRESENT
Seashore Software
  • Founded my own consulting company in 2006, and since then, have been doing a mix of independent projects and client work.
  • Acted as both a technical leader and hands-on developer, I delivered a variety of apps for mobile, the web, and the enterprise.
  • Developed custom software for companies ranging in size from one-person start-ups to Fortune 50 multinationals.
  • Worked on a variety of projects in a number of industries; for more details, please see my portfolio.
Technologies: Android, iOS, Django, Java, C++, Objective-C, Swift, Python, React, React Native, Node.js, TypeScript, JavaScript, Kotlin, Unit Testing, REST APIs, Android App Design

Senior Firmware Engineer

2004 - 2006
Gemstar | TV Guide Onscreen
  • Designed and wrote embedded real-time software in C for an electronic program guide (EPG) for televisions, DVD recorders, DVRs, and more.
  • Developed graphical debugging tools in C# .NET using advanced features such as remoting and multithreading.
  • Worked directly with multinational customers to integrate the TV Guide Onscreen EPG into their products.
  • Acted as the lead engineer for several integration projects.
  • Contributed to onsite meetings and weekly international conference calls.
  • Designed and developed an automated test suite in Python and C#.
  • Worked in a large international team.
Technologies: C#.NET, .NET, Firmware, Python, C#, C, Unit Testing, REST APIs

Senior Software Engineer

2001 - 2004
Juniper Networks (formerly Unisphere)
  • Designed and developed embedded software in C and C++, using the VxWorks RTOS.
  • Worked on control processor software for the following network protocols: SONET, DS3, DS1, HDLC, and Ethernet.
  • Designed and implemented low-level device drivers.
  • Brought up and debugged new hardware, including PCI controllers, network interface controllers, and custom FPGAs and ASICs.
  • Developed system-level software for redundancy, hardware monitoring, CLI interactions, and software downloads.
  • Collaborated with hardware engineers, testers, and customers.
Technologies: Firmware, Networking, VxWorks, C++, C, Unit Testing

Software Engineer

2001 - 2001
Starent Networks
  • Developed software in C, C++, and Perl for a Linux platform as part of a startup company creating the next generation of high-speed mobile wireless infrastructure (3G wireless).
  • Designed and implemented the system startup sequence and dynamic task creation sequence for a large-scale, carrier-class networking product.
  • Designed and implemented a software simulation environment in the Linux operating system—to simulate the entire software system on a desktop PC.
  • Wrote performance-critical embedded software.
  • Worked within a standard of "five-nines" reliability (99.999% uptime).
Technologies: Perl, Wireless, Embedded Linux, C++, C, Unit Testing

Software Engineer Level Two

1999 - 2000
Arris Interactive (formerly part of Nortel Networks)
  • Developed embedded software in C, C++, and assembly (MIPS and PowerPC) for DOCSIS 1.1 broadband cable devices (data and voice over cable television lines). Worked as part of a multi-site team developing large-scale carrier-grade equipment.
  • Ported a large base of software from the Nucleus Plus embedded operating system to VxWorks 5.4.
  • Designed and developed low-level device drivers for Broadcom and Texas Instruments controller chips.
  • Developed a suite of automated test scripts written in Tcl on a Linux server, utilizing Netcom Smartbits network testing devices.
  • Worked in the office that was the original inventor of the cable modem.
Technologies: Firmware, Embedded Software, Assembly, C++, C, Unit Testing

Teaching Assistant

1998 - 1999
Harvard University Extension School
  • Taught an advanced-level C++ programming class.
  • Mentored 30 students for one hour per week.
  • Graded projects and tests.
  • Held office hours to assist students with assignments.
Technologies: Teaching, C++, Unit Testing


1998 - 1999
MERL | A Mitsubishi Electric Research Laboratory
  • Researched and developed electronic devices: self-describing building blocks. The project was presented at Siggraph 2000.
  • Created a graphical application in OpenGL and Visual C++.
  • Developed embedded software in PIC Assembly Language.
  • Was named as a co-inventor for two patents.
Technologies: Paid in Capital (PIC), OpenGL, C++, Unit Testing

Technical Lead | Mobile, Web, and Back-end Services for Anthem Health

Anthem is the largest health insurance provider in the USA.

Work Done:
• Led a team to implement a large feature-set for Anthem's Medicaid mobile app using React Native
• Led a team implementing the full stack of the Anthem.AI developer portal using Node.js and React
• Worked as a lead engineer on Anthem's flagship mobile app, developed natively using Kotlin for Android and Swift for iOS
• Developed the back-end services in Node.js connecting to MongoDB and PostgreSQL databases

Cross-platform iOS and Android App for DivX

Built an innovative video streaming and sharing app.

Work Done:
• Collaborated with a small team within a larger organization
• Developed React Native code in JavaScript
• Built a native Android code in Java and Kotlin
• Developed native iOS code in Swift and Objective-C
• Handled and implemented live video streaming using WebRTC
• Implemented advanced video capture, transcoding, and streaming

iOS and React Native for Hashletes

Created a next-generation fantasy sports app.

Work Done:
• Worked in a fast-paced startup atmosphere
• Developed React Native and JavaScript, Objective-C, and Swift code for a visually stunning iOS app
• Collaborated with a remote team across several time zones
• Integrated multiple payment methods, including PayPal and credit card

iOS App for Rexel

With over $14 billion in annual revenue, Rexel is a Fortune 500 company that sells electrical equipment under many brand names around the globe.

Work Done:
• Led a team to develop new features, fix bugs, and streamline the code for Rexel's native iOS app
• Implemented internationalization and custom branding for 14 of Rexel's brands, using a shared Swift code-base

Elegant iOS Fitness Tracking App

Evolve is a feature-rich fitness tracking app for iOS.

Work Done:
• Bootstrapped the iOS development environment using the Swift language, the Parse platform, and modern mobile technologies.
• Developed a natural language processing library for voice recognition.
• Implemented a beautiful user interface design.
• Wrote a large percentage of the shipping code.

Custom macOS App for Acadia Shutters

Acadia is an Atlanta-based company that sells and installs custom window blinds and shutters. They needed a tool to help their sales reps create complex orders that encompassed many different window types, sizes, and products. The app also created installation instructions, product orders, and invoices.

Work Done:
• Developed code in Objective-C for an app for the sales reps to use on customer premises.
• Implemented complex multithreaded routines to enable background network synchronization.
• Implemented custom-designed user interface components.
• Cleaned up, fixed, and improved legacy code.
• Filled in unit tests, including automated user interface tests.

The Guitarator Suite of Apps

The ultimate guitar reference tools for multiple platforms. It's available as native apps for Windows, Mac OS X, Android, iPhone, and iPad; plus it is also free as online web apps.

Users can learn how to play any chord or scale in any tuning, or perform an advanced "reverse chord lookup" to find the proper name for invented chords.

The apps include multimedia playback, audio analysis, and a precisely timed metronome.

Tac! iOS App

I was brought into a project where the client was unhappy with the state of the code. I worked with them to quickly clean it up and bring the app to a fully functional state.

The app is a unique twist on classic tic-tac-toe, with networked multiplayer capabilities, in-app purchases, and a custom user interface involving slick animations.

Loop Lingo

Loop Linogo is a social marketing solutions platform with a number of features.

Loop Linogo Features:
• Customers of online merchants earn rewards by sharing with friends via Facebook, Twitter, Google+, or email.
• Customized back-ends for merchants, sales reps, and customers.
• Detailed tracking and statistics.

Work Done:
• Implemented the back end in Python and with the Django framework
• Integrated it with Facebook and other social network APIs.
• Built the UI using various front-end technologies, including AngularJS, Bootstrap, and modern JavaScript and HTML5.

Play Scopa

I created a multiplayer version of a traditional Italian card game.

Work Done:
• Developed in Python using the Django framework.
• Implemented real-time networked gameplay.
• Uses AJAX and Comet technologies to provide browser-based instant notifications.
• Developed a sophisticated JavaScript and HTML5-based animation.
• Implemented authentication via Facebook and OAuth2.

Usability Test Software for NIST

I created a Windows desktop application in C# for NIST (the National Institute of Standards and Technology and Usability Works).

The application presented a dynamic, customizable, graphical user interface to a questionnaire and usability test. The program logged in results and created reports based on users' responses.


NexTalk provides video-streaming software for on-demand translators. It is used in performance-critical locations such as hospital emergency rooms.

I migrated the client's software from a proprietary and obsolete video conferencing platform to a new one based on modern standards such as WebM and SIP. This involved understanding a large legacy codebase of C++ and enhancing it in a forward-thinking way without breaking any legacy functionality.


C, Swift, Python, Objective-C, JavaScript, Python 2, Python 3, Kotlin, C++, Scheme, Java, CSS, HTML5, Perl, C#, C#.NET, TypeScript, Assembly, Ruby


Django, iOS SDK, React Native, UIKit, Redux, .NET


Node.js, REST APIs, React, OpenGL, WebRTC


Functional Programming, Asynchronous Programming, Model View Viewmodel (MVVM), Unit Testing, Agile, DevOps, DSDM


Android, iOS, iOS 11, iOS 12, iOS 10+, MacOS, Windows, Linux, Embedded Linux, VxWorks, Apple, Bluetooth LE


Embedded Software, iPhone, Team Leadership, Full-stack, Architecture, Android App Design, React Native Bridge, Digital Signal Processing, Audio Processing, APIs, Video Streaming, Kotlin Multiplatform, Paid in Capital (PIC), Firmware, Wireless, Networking, Ethernet, Synchronous Optical Networking (SONET), Design, Leadership, PayPal, Digital Payments, IT Management


PostgreSQL, MySQL


Photoshop CC, Sketch

Industry Expertise


1995 - 1999

Bachelor of Science Degree in Computer Engineering

Tufts University - Medford, MA, USA