Roman Meszaros, Developer in Hook, United Kingdom
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Roman Meszaros

Verified Expert  in Engineering

Full-stack Developer

Hook, United Kingdom
Toptal Member Since
February 25, 2022

With over five years of industry experience, Roman is a full-stack developer specializing in JavaScript, TypeScript, and all things React. He started his career as an ERP developer for Asseco Solutions. Most recently, he has volunteered with a team that provides a CMS solution for hundreds of language communities where he works in a fully remote team. Given Roman's experience with SQL databases and back-end development, he is also a valued member of teams developing multi-tiered solutions.


Kalaam Media
Drupal, HTML, CSS, JavaScript, jQuery, MySQL, Git, Linux, Bitbucket, Agile...
Corsali, Inc.
TypeScript, JSON, SQL, JavaScript, GitHub, HTML, CSV, Scrum...
Gratex International
Java, JSON, Git, Eclipse IDE, Oracle Forms, Oracle SQL, Back-end, APIs, Regex...




Preferred Environment

Windows, Visual Studio Code (VS Code), PHP, Drupal, React, MySQL, Next.js, TypeScript, Git

The most amazing...

...way I was able to help with my skills is by supporting hundreds of language communities around the world with their own digital space.

Work Experience

Drupal Programmer

2021 - PRESENT
Kalaam Media
  • Developed a full-stack sorting assistant solution fully as part of a larger Drupal-based project. The sorting assistant uses a React front end, Drupal JSON web services, and the appropriate SQL database structures I designed.
  • Used the Agile methodology and Trello boards to communicate with the client services team and track and fix bugs.
  • Developed a Drupal module for displaying website status. The module helps website managers quickly check the readiness of websites, check for bugs, and launch the websites more efficiently.
  • Refactored and optimized existing code, developed additional functionality, and communicated with the client about their needs. The flagship product, Wildfire, is deployed on almost 1,000 websites supporting minority communities around the globe.
Technologies: Drupal, HTML, CSS, JavaScript, jQuery, MySQL, Git, Linux, Bitbucket, Agile, React, RESTful Services, Webpack, NPM, Trello, Regex, Composer

TypeScript Developer

2022 - 2022
Corsali, Inc.
  • Processed different data formats, such as JSON, CSV, and HTML, and converted them into SQL for a data marketplace company.
  • Helped develop unit tests and provided advice on using certain advanced JavaScript features (Promises and Proxies) to improve the developers' experience and achieve correct results.
  • Discussed the project's progress with an assigned developer, submitted my results to GitHub and managed multiple branches with my preliminary work.
Technologies: TypeScript, JSON, SQL, JavaScript, GitHub, HTML, CSV, Scrum, Regular Expressions, Regex

Java Programmer

2012 - 2014
Gratex International
  • Transformed an existing insurance system from Oracle Forms into a full-stack solution while preserving the original database structures and enabled a smooth transition to new technologies and better support for thousands of employees.
  • Analyzed Oracle PL/SQL codebase and transformed that into web services within a Java solution with the Spring framework.
  • Provided valuable feedback and mediator between SQL specialists and Java back-end developers when transforming different types of Oracle-specific PL/SQL structures and developed the parts of the custom SQL engine for handling these.
  • Developed a module for creating templates for insurance policies.
  • Used Git to track codebase changes and manage the software's development and deployment versions.
  • Developed RESTful web services in a Java back end using a custom JSON Schema validation.
Technologies: Java, JSON, Git, Eclipse IDE, Oracle Forms, Oracle SQL, Back-end, APIs, Regex, REST APIs


2008 - 2010
Asseco Solutions Slovakia
  • Developed Oracle XML web services, which allowed clients to use API calls and third-party apps to communicate with the ERP core.
  • Tracked and fixed bugs using Jira as a tracking tool.
  • Supported the main product, a stateful desktop application developed with PowerBuilder and connected to the core Oracle database.
  • Changed the clients' custom solutions and forms to conform with EU regulations for displaying prices when introducing the Euro currency in Slovakia. This affected all the clients of the company.
Technologies: PowerBuilder, Oracle PL/SQL, XML Web Services, Back-end, Oracle SQL, CVS

AI Agent Learning Game Strategy Using Neural Networks with Reinforcement Learning

An AI agent that learned a strategy of a board game. I designed the game environment for the agent to learn in and a rule-based agent that the AI learned from. The AI agent used feedforward neural networks and reinforcement learning, and I trained the AI agent against different rule-based agents. I designed this as part of my dissertation project.

Sorting App for Ordering Manuscript Reliability

A full-stack addition to an existing Drupal module. The project started with the client's initial idea and research. The goal was to support researchers when working with ancient manuscripts, enabling them to order different manuscript readings according to their reliability.

I designed the app to guide researchers when ordering manuscripts. The ordering happened in two steps: bucket sort and merge sort. In each step, the researchers made the atomic decisions to put an item into a category or compare two items as the app was prompting them to make the relevant decisions. I designed the algorithms and database structures and created RESTful API services and the React front-end app.

Board Game Website

A personal study project, building a full-stack multiplayer board game website. The game front end is created using React. The back end was done in PHP using the CakePHP framework. The back end exposed restful API services to which the front end connected. The app was based on an actual board game.

Toptal React Accelerator
The Toptal React Accelerator is an exclusive learning program that educates JavaScript developers in React, NextJS, Redux, and GraphQL. This is a 2-month program that consists of rigorous learning exercises and hands-on activities, a stringent evaluation process, comprehensive learning assessments, and 30-40 hours of building an Invoice Management System. Users can track invoices, clients, and company information within this invoicing application.
2007 - 2012

Master's Degree in Software Engineering

Slovak University of Technology - Bratislava, Slovakia


Toptal Node.JS Accelerator Graduate

Toptal, LLC


Toptal React Accelerator Graduate

Toptal, LLC


React, Node.js, jQuery, REST APIs, React Hook Form, Yup, React Router, React Redux


JSX, Git, Bitbucket, GitHub, Eclipse IDE, Oracle Forms, Webpack, NPM, Trello, Composer, CVS


Material UI, CakePHP, Express.js, Next.js, Windows Presentation Foundation (WPF), Unity3D, Jest, Cypress, Redux


SQL, PHP, JavaScript, TypeScript, Regex, C#, HTML, CSS, Java, PowerBuilder, C#.NET, Sass, Less, GraphQL


Object-oriented Programming (OOP), Agile, Scrum


JSON, Oracle SQL, MySQL, Oracle PL/SQL


Drupal, Visual Studio Code (VS Code), Linux, Windows, Amazon Web Services (AWS)


Front-end, RESTful Services, Full-stack, Back-end, APIs, Axios, XML Web Services, Neural Networks, Reinforcement Learning, Genetic Algorithms, Interpretation, Communication, Translation, Leadership, Board Games, WebSockets, CSV, Regular Expressions

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