Rado Fulek, Software Developer in Midland Park, NJ, United States
Rado Fulek

Software Developer in Midland Park, NJ, United States

Member since July 28, 2021
Rado is a developer with versatile programming and problem-solving skills and four years of software development experience. Furthermore, he conducted cutting-edge research about graph algorithms and published 50+ research articles. His main strengths are in back-end development, but his diverse professional experience allows him to work efficiently on the front end. Rado's industry experience is backed by a bachelor's and master's degree in computer science and a PhD in mathematics.
Rado is now available for hire




Midland Park, NJ, United States



Preferred Environment

Visual Studio Code, IntelliJ IDEA, Microsoft Visual Studio

The most amazing...

...thing I've done is discovering the first fast algorithm for the clustered planarity problem, which was open for 25 years.


  • Senior Back-end Developer

    2021 - 2022
    Comity Inc
    • Designed and implemented back-end service modules for a fintech app deployed to AWS based on Java and Kotlin, including integration and unit tests.
    • Built API clients and workflows for processing financial transactions based on the Plaid and Galileo API in the back end of a fintech app.
    • Executed automatic messaging infrastructure based on Courier API in the back end of a fintech app.
    • Created admin tools for a fintech app in Retool, allowing monitoring of events and managing and uploading documents.
    • Performed regular code reviews and actively participated in brainstorming sessions to identify product improvements.
    • Contributed to a Python module for extracting information from tax forms based on Amazon Textract.
    Technologies: Kotlin, PostgreSQL, Dagger 2, Javalin, Git, AWS DevOps, IntelliJ, Ubuntu Linux, JavaScript, Retool, Plaid API, Gradle, Maven, Software Engineering, Back-end Development, Web Development, IntelliJ IDEA, Fintech, XML, Liquibase, REST APIs, Object-relational Mapping (ORM), Back-end, Linux, Amazon Web Services (AWS), Swagger, OpenAPI, APIs, REST, JSON Web Tokens (JWT), JSON, SMS, API Integration, Online Payments, Webhook, Docker, Low Code, Low-code Development, Data Processing, Python, Debugging, User Interface (UI), Software Development, Plaid, Databases, OAuth 2, Integration Testing, Mockito, Ubuntu, JUnit, Java 11, GitOps, Web Security, Technical Writing, Technical Documentation, API Documentation
  • Visiting Faculty

    2020 - 2021
    University of California San Diego
    • Taught online undergraduate-level courses on calculus, probability theory, and applied mathematics.
    • Organized guest lectures for students given by experts working in the industry.
    • Prepared study materials and pre-recorded lectures for online courses.
    • Published a research paper in the Symposium on Computational Geometry, the leading venue in computational geometry.
    • Managed teaching assistants who led discussion sessions in my classes and graded students' work.
    Technologies: Applied Mathematics, Calculus, Probability Theory, Combinatorics, Graph Theory, Computational Geometry, Communication, Quantitative Analysis, Mathematics, LaTeX, Presentations, Microsoft Excel, Microsoft Word, PDF, 3D Math, Vectors, Geometry, Learning Management Systems (LMS), Bayesian Statistics, Statistics, Spreadsheets, Technical Writing, Writing & Editing
  • Research Fellow

    2013 - 2020
    Columbia University, IST Austria, University of Arizona
    • Resolved several long-standing open problems that withstood serious attacks from leading experts in computational geometry.
    • Improved the best-known quantitative estimates relaxing Conway's thrackle conjecture with a computer-assisted proof implemented in C++.
    • Confirmed experimentally the feasibility of a novel network visualization algorithm by its implementation in Python.
    • Created an educational application in Java, illustrating several phenomena pertaining to the geometric representation of graphs and circle packings.
    • Researched the connection between cascade and graphical models of influence spread over networks.
    • Published several research articles in the proceedings of leading venues on algorithms and computational geometry: ACM-SIAM Symposium on Discrete Algorithms (SODA) and Symposium on Computational Geometry (SoCG).
    • Invited to the program committee of the 24th, 26th, and 28th International Symposium on Graph Drawing and Network Visualization.
    Technologies: Computer Science, Applied Mathematics, Combinatorics, Python, Combinatorial Optimization, Graph Theory, Computational Geometry, Algorithms, Communication, Software, Mathematics, Data Science, LaTeX, Geometry, 3D Math, Algebra, Quantitative Modeling, Data Pipelines, C++, Java, Presentations, Technical Writing, Writing & Editing
  • Junior Developer

    2004 - 2006
    • Implemented a substantial part of the initial release of the first flight reservation website in Slovakia, pelikan.sk, based on ASP.NET and mainly written in C#.
    • Built a desktop application as a user interface for a standalone database in Delphi with Object Pascal.
    • Implemented a substantial part of the initial release of slovakia.travel information portal based on ASP.NET and mainly written in C#.
    Technologies: ASP.NET, Delphi, SQL, JavaScript, HTML, Object-oriented Programming (OOP), Software, Object Pascal, Software Engineering, Back-end Development, Web Development, C#.NET, .NET, Microsoft Visual Studio, C#, Windows, XML, Object-relational Mapping (ORM), Multithreading, Back-end, API Integration, Debugging, User Interface (UI), Relational Database Design, Software Development, Databases


  • iGraph

    iGraph is a popular C/C++ library for complex network analysis, emphasizing efficiency, portability, and ease of use.

    I designed and integrated a module for generating triangulated meshes and their duals. Furthermore, I improved by order of magnitude the running time of implementing functionality for computing distances in graphs through a recently discovered heuristic and advanced optimization techniques.

  • Fintech App

    A Kotlin-and-React-Native-based app facilitating payments of advance tax credits. I was primarily a back-end developer in charge of integrating payment providers, messaging infrastructure and implementing admin tools based on Retool.

  • Toptal React Academy

    The Toptal React Academy is an exclusive learning program that teaches the React framework to select members of the Toptal network. After a month of study, all graduates are tasked with completing a 30-40 hour final project to build and deliver a React app from scratch.

  • Angular Energy for Graph Visualizations

    Designed and experimentally confirmed the feasibility of a novel network visualization algorithm using Python. The algorithm combines the technique of gradient descent and a novel notion of angular energy in drawings of networks.

  • Flight Reservation Web Application

    Built the front end and back end for a flight reservation web application based on ASP.NET and Amadeus flight reservation system. The bulk of my work was integrating Amadeus with the rest of the booking engine.

  • Spring Embeddings and Circle Packings

    Created an educational application in Java that illustrates several phenomena pertaining to geometric representation of graphs and circle packings. The application illustrates the interplay between the so-called spring embeddings of graphs and their representations by touching disks.

  • Atomic Embeddability, Clustered Planarity, and Thickenability

    Resolved the clustered planarity problem that concerns a graph together with a hierarchical clustering on its vertices. This result has numerous immediate implications for algorithmic problems in the area of graph algorithms and has already inspired numerous follow-up research projects. The result was announced at the 2020 ACM-SIAM Symposium on Discrete Algorithms (SODA) and published by the highly respected Journal of the ACM.

  • YouTube Transcripts Summarizer

    Developed from scratch an extension to the Chrome browser that summarizes YouTube transcripts and provides a user-friendly GUI to adjust the parameters of the summary. The extension fetches video transcripts using URLs extracted from the HTML source and summarizes them by calling OpenAI API.

  • NetworkX

    NetworkX is a popular Python library for studying graphs and networks. I improved the implementation of an algorithm finding an optimal traversal in a graph concerning edge weights and suggested further improvements for the performance.

  • Quinde Foundation

    Back-end development on Quinde's Learning Management System MVP. I researched and architected the user authentication flow and authorization methods and developed a mocking solution for the back-end API. Also, synchronized work between front-end and back-end developers.


  • Languages

    Python, Java, C#.NET, C, C++, Kotlin, SQL, Delphi, JavaScript, HTML, Object Pascal, C#, XML, PHP, Java Persistence Query Language (JPQL), CSS, Java 11, GraphQL
  • Other

    Combinatorics, Graph Theory, Computational Geometry, Data Structures, Algorithms, Computer Science, Mathematics, Software Engineering, Back-end, Algebra, Combinatorial Optimization, Linear Algebra, Languages, Applied Mathematics, Probability Theory, University Teaching, Presentations, Communication, APIs, Software, Back-end Development, Matrix Algebra, Technical Writing, Writing & Editing, Technical Documentation, API Documentation, Computational Topology, Complexity Theory, Regular Expressions, Amadeus, Operations Research, Probabilistic Graphical Models, Neural Networks, Bayesian Inference & Modeling, AWS DevOps, Retool, Quantitative Analysis, Web Development, Fintech, Multithreading, Full-stack, SMS, Artificial Intelligence (AI), WebSockets, API Integration, Serverless, PDF, Online Payments, Webhook, Front-end, Low Code, Data Processing, Debugging, Geometry, 3D Math, User Interface (UI), Learning Management Systems (LMS), Relational Database Design, CI/CD Pipelines, Quantitative Modeling, Software Development, Bayesian Statistics, Statistics, Cloud Services, Cloud Infrastructure, Cloud Architecture, Integration Testing, Chrome Extensions, OpenAI API, ES6 Promises, GitOps, Web Scraping, AWS RDS, AWS SAM, Amazon API Gateway, AWS Cognito, Web Security, Vectors, Calculus, AWS Cloud Architecture, Networking, Code Deployment, Codebase Development
  • Libraries/APIs

    React, Matplotlib, NumPy, REST APIs, SciPy, Pandas, Plaid API, Liquibase, OpenAPI, Node.js, Asyncio, PySpark
  • Tools

    LaTeX, IntelliJ, IntelliJ IDEA, Spring Tool Suite (STS), Visual Studio .NET, Microsoft Visual C++, Jupyter, Git, Gradle, Maven, Microsoft Visual Studio, Microsoft Excel, Microsoft Word, Spreadsheets, Plaid, Cloud Dataflow, GitHub, Prism
  • Paradigms

    Object-oriented Programming (OOP), Object-relational Mapping (ORM), Parallel Computing, Data Science, REST, Low-code Development, Serverless Architecture, Unit Testing
  • Platforms

    Windows, Ubuntu Linux, Amazon Web Services (AWS), Visual Studio Code, Firebase, Linux, Docker, AWS Lambda, AWS Cloud Computing Services, Google Cloud Platform (GCP), Ubuntu, Amazon EC2
  • Storage

    Databases, Relational Databases, MySQL, JSON, PostgreSQL, NoSQL, Amazon S3 (AWS S3), Amazon DynamoDB, Data Pipelines, Google Cloud
  • Industry Expertise

    Network Security
  • Frameworks

    Spring Boot, ASP.NET, Dagger 2, Javalin, Spring, .NET, Swagger, JPA, Hibernate, JSON Web Tokens (JWT), Flask, Django, Selenium, OAuth 2, Mockito, JUnit


  • PhD in Mathematics
    2008 - 2012
    Swiss Federal Institute of Technology - Lausanne, Switzerland
  • Master's Degree in Computer Science
    2006 - 2008
    Simon Fraser University - Burnaby, BC, Canada
  • Bachelor's Degree in Computer Science
    2000 - 2005
    Comenius University - Bratislava, Slovakia


  • AWS Solutions Architect Professional
    MARCH 2023 - MARCH 2026
    Amazon Web Services
  • AWS Solutions Architect Associate
    DECEMBER 2022 - DECEMBER 2025
    Amazon Web Services
  • AWS Certified Developer - Associate
    Amazon Web Services
  • Toptal React Academy Graduate
    Toptal, LLC

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