Nicholas Hadjiminas, Developer in Nicosia, Cyprus
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Nicholas Hadjiminas

Verified Expert  in Engineering

Bio

Nicholas is a dedicated and efficient full-stack developer with over 10 years of hands-on experience in software design and development. He has an extensive background in the entire software development lifecycle, including design, development, debugging, testing, and maintenance of web and mobile applications. Nicholas has in-depth knowledge of software architecture, development techniques, object-oriented design, design patterns, and Agile methodologies.

Portfolio

Lab4Crypto
Rust, React, MongoDB, Next.js, API Development, X (formerly Twitter) API...
Electricity Authority of Cyprus
Node.js, Rust, JavaScript, TypeScript, REST, GraphQL, MongoDB, Angular, React...
IOT LTD
Node.js, JavaScript, TypeScript, Vue, HTML5, CSS, PostgreSQL, Firebase...

Experience

  • Software Development - 12 years
  • PostgreSQL - 7 years
  • TypeScript - 6 years
  • Node.js - 5 years
  • GraphQL - 4 years
  • MongoDB - 3 years
  • Rust - 2 years
  • React - 2 years

Availability

Full-time

Preferred Environment

Rust, MongoDB, React, GraphQL

The most amazing...

...product I've developed is a transition market arrangement system that runs an electricity transmission market in Cyprus.

Work Experience

CTO

2022 - PRESENT
Lab4Crypto
  • Developed the Lab4Crypto application, a comprehensive platform offering detailed statistics for cryptocurrencies. The app operates on a subscription-based model with a monthly fee.
  • Focused on back-end development. Utilized Rust to build high-performance GraphQL APIs, ensuring efficient data retrieval and manipulation.
  • Worked on front-end development. Crafted a user-friendly interface using Next.js, enhancing user experience and engagement.
  • Contributed to database management. Implemented MongoDB for robust and scalable data storage solutions.
  • Integrated Stripe for efficient and secure subscription payments seamlessly.
  • Oversaw the launch process and ongoing management of Lab4Crypto. The app attracted over 100,000 daily visits. Played a pivotal role in ensuring the project's success by maintaining high performance, security, and user satisfaction.
  • Built and maintained a suite of web scraping pipelines to aggregate real-time data from multiple cryptocurrency exchanges and financial news sources, ensuring the platform remained up-to-date and competitive.
  • Developed custom scrapers using Python for high-throughput data extraction from both public APIs and HTML-based sources, handling rate limits and anti-bot mechanisms.
  • Performed data enrichment by cross-referencing scraped data with third-party APIs (e.g., CoinGecko, CoinMarketCap) to fill in gaps, normalize datasets, and enhance analytics quality.
Technologies: Rust, React, MongoDB, Next.js, API Development, X (formerly Twitter) API, Full-stack Development, ChatGPT API, ChatGPT, Data Science, Databases, Code Review, Data Preprocessing, Feature Engineering, Backtesting Trading Strategies, LightGBM, XGBoost, Scalable Architectures, Concurrency, Data Analytics, Chatbots, Technical Writing, System Architecture, Algorithmic Trading, Leadership, Decentralized Systems, Networking, Plotly, OpenAI, Trading, Trading Bots, Trading Systems, Material UI, API Design, Large Language Models (LLMs), CTO, Docker, Object-oriented Programming (OOP), Stripe API, Fintech, Minimum Viable Product (MVP), OpenAI API, Social Media Integration, Software Design, Technical Leadership, API Testing, Financial Reporting Dashboards, Stripe Checkout, Stripe reporting, Data Engineering, Data Visualization, Python API, Containerization, Augmented Reality (AR), Unity3D, Automated Trading Software, Document Parsing, Data Enrichment, Datasets, AI Automation, Digital Payments, Excel 365, Finance APIs, AI Agents, Payment APIs, User Authentication, Front-end Development, Reinforcement Learning, Prompt Engineering, Security, Stripe Connect API, Facebook API, Meta Ads, Instagram API, API Databases, Deployment, Accessibility, Slack

Senior Full-stack Developer

2018 - 2022
Electricity Authority of Cyprus
  • Led the development of a transition market arrangement system, which runs an electricity transmission market in Cyprus.
  • Directed the development of an electricity production forecasting tool, a web-based system used to forecast the amount of electricity produced by wind and solar parks in Cyprus.
  • Developed several Python applications used to automate an organization's internal procedures.
  • Served as a full-stack developer using modern technologies, including Node.js, Rust, JavaScript, TypeScript, GraphQL, MongoDB, Angular, and React.
  • Developed automation solutions that scraped and processed data from external sources (including market management systems and APIs), transforming it into structured formats like Excel and XML for reporting and analysis.
  • Automated the normalization and transformation of raw data for seamless integration into internal tools and dashboards.
  • Built Python-based scrapers to collect energy market and regulatory data, supporting forecasting and compliance workflows.
Technologies: Node.js, Rust, JavaScript, TypeScript, REST, GraphQL, MongoDB, Angular, React, Oracle, Cloudflare, Amazon Web Services (AWS), Web Applications, Full-stack, HTML, NoSQL, DevOps, APIs, REST APIs, Next.js, Mobile, Architecture, Python, DevOps Engineer, Express.js, Data Cleaning, Data Organization, JSON, API Integration, Stripe, Google Analytics, Web UX, Web Development, Software Architecture, Back-end Development, Back-end, Back-end Architecture, Project Management, Proof of Concept (POC), CSV, Microsoft Excel, ESLint, Linux, Process Automation, PDF, Database Architecture, Data Structures, Web Design, Software Integration, GitHub, Analytical Dashboards, User Interface (UI), User Experience (UX), XML, Machine Learning, AngularJS, Data Analysis, Automated Data Flows, Selenium, Artificial Intelligence (AI), Vercel, Windows, Automation, API Development, Full-stack Development, Algorithms, Databases, Code Review, Scalable Architectures, Concurrency, Data Analytics, Technical Writing, System Architecture, Leadership, Decentralized Systems, Networking, Image Recognition, NestJS, Front-end, Material UI, WebView, API Design, XML Parsing, Tailwind CSS, Data Integration, Object-oriented Programming (OOP), Minimum Viable Product (MVP), Software Design, Technical Leadership, Postman, cURL, API Testing, Email Automation, Data Visualization, Python API, Email Parsing, Excel Macros, Excel 365, LocalStorage, User Authentication, Front-end Development, SMS, Security, Active Directory (AD), Windows PowerShell, Windows Desktop, Windows Desktop Software, API Databases, Deployment, Accessibility, Slack

Senior Software Engineer

2016 - 2018
IOT LTD
  • Coordinated designing, developing, and delivering an innovative online food ordering system.
  • Designed and performed a usability study to evaluate users' experience as part of user-centered design and ensure the smooth development of a system.
  • Handled installation and maintenance of Linux and Windows servers.
  • Scraped and processed address data, including postal codes and coordinates, to build a location-based API for address search and map visualization.
  • Automated the normalization and validation of location data to ensure accurate geolocation and seamless user experience on the map interface.
Technologies: Node.js, JavaScript, TypeScript, Vue, HTML5, CSS, PostgreSQL, Firebase, Amazon CloudFront CDN, Amazon S3 (AWS S3), Amazon Glacier, NGINX, Amazon Web Services (AWS), Cloudflare, Web Applications, Full-stack, Scrum, Jira, HTML, DevOps, Sass, APIs, Mobile Apps, Android, iOS, Mobile App Development, Python, Web Scraping, Data Organization, Stripe, Google Analytics, QR Codes, Web Development, Websites, Software Architecture, Data Scraping, Back-end Development, MVP Design, Project Management, Proof of Concept (POC), .NET, C#, .NET Core, Single Sign-on (SSO), Microsoft Excel, ESLint, Linux, Process Automation, PDF, Architecture, Database Architecture, Data Structures, Agile, CI/CD Pipelines, Scraping, Selenium, Google Workspace, Web Design, GitHub, SQL, Twilio API, Analytical Dashboards, Twilio, User Interface (UI), User Experience (UX), Microservices, Natural Language Processing (NLP), Machine Learning, SaaS, Google Cloud, Blockchain, Open Source, Integration, Website Data Scraping, Windows, API Development, DigitalOcean, Bots, Algorithms, Databases, Code Review, Scalable Architectures, Concurrency, Technical Writing, System Architecture, Leadership, React Native, Front-end, API Design, ERD, Object-oriented Programming (OOP), Fintech, Mobile App Design, Minimum Viable Product (MVP), Software Design, Technical Leadership, Postman, cURL, API Testing, Email Automation, Headless CMS, Maps, Data Visualization, OAuth, Design, Amazon EC2, Finance APIs, Purchase Orders, AWS Lambda, User Authentication, Front-end Development, SMS, Security, Low Code, Windows PowerShell, Windows Presentation Foundation (WPF), Windows Desktop, Windows Desktop Software, WinAPI, API Databases, Google Maps API, Amazon CloudFront, Deployment, WebSockets, Accessibility, Cloud Firestore, Firebase Authentication

IT and Systems Administrator

2012 - 2016
Cyprus State General Laboratory
  • Developed and led the maintenance of several applications needed for carrying out projects assigned to the State General Laboratory by the European Food Safety Authority.
  • Handled the maintenance of Windows, Linux, Internet Information Services (IIS) web, and SQL servers.
  • Designed, implemented, and managed maintenance of the laboratory's back-up system.
Technologies: C, C#.NET, Java, Git, ASP.NET, MySQL, PostgreSQL, Web Applications, HTML, DevOps, REST APIs, Python, DevOps Engineer, Data Cleaning, Data Organization, API Integration, Web UX, Software Architecture, Back-end, Back-end Architecture, Database Migration, MVP Design, .NET, C#, .NET Core, CSV, Microsoft Excel, Linux, Process Automation, Web Design, GitHub, Azure, XML, Data Analysis, Data Entry, Automated Data Flows, Windows, DigitalOcean, Algorithms, Concurrency, Technical Writing, Networking, Object-oriented Programming (OOP), Software Design, IT Security, cURL, Email Automation, Document Parsing, Excel Macros, Active Directory (AD), Windows Presentation Foundation (WPF), Windows Desktop, Windows Desktop Software, WinAPI, Azure DevOps

Software Engineer

2008 - 2010
CSPL Computers Ltd.
  • Designed a solution following customers' requirements. Developed and implemented software solutions to ensure compliance with established guidelines.
  • Created business applications in web-based environments. Designed and developed corporate websites and online shops, including integrating local payment gateways and legacy enterprise resource planning (ERP) systems.
  • Managed a hosting environment for various systems, including virtualization, VMware, a firewall, Windows and Linux server configuration, a disaster recovery plan, Amazon S3 Glacier backups, files, a database, and operating system image backups.
  • Built scrapers and data collectors for syncing eCommerce platforms with stock systems, handling a wide variety of formats and endpoints (web-based and API-based).
  • Enriched product data by linking it with vendor databases to ensure accurate inventory synchronization and product listings.
Technologies: Microsoft Certified Solutions Developer .NET 4.5 Web Applications Developer, PHP, MySQL, Debian Linux, Apache, SQL, Web Applications, HTML, Amazon Web Services (AWS), APIs, REST APIs, Mobile Apps, Android, Mobile App Development, Mobile, Architecture, DevOps Engineer, Web Scraping, Data Cleaning, Data Organization, JSON, API Integration, CRM APIs, Customer Relationship Management (CRM), Google Analytics, Web UX, Web Development, Websites, Software Architecture, Data Scraping, OAuth 2, Back-end Development, Back-end, Back-end Architecture, Database Migration, MVP Design, Proof of Concept (POC), .NET, C#, CSV, Microsoft Excel, Linux, PDF, Optical Character Recognition (OCR), ASP.NET, Database Architecture, Data Structures, Agile, Scraping, Web Design, Software Integration, Analytical Dashboards, User Experience (UX), XML, SQL Server 2017, Automated Data Flows, Open Source, Integration, Website Data Scraping, Automation, API Development, Bots, Algorithms, Mobile Applications, Databases, Concurrency, eCommerce, XML Parsing, ERD, Web Crawlers, Data Integration, Object-oriented Programming (OOP), Software Design, API Testing, Headless CMS, Maps, OpenCart, Unity, Commerce, POS, Digital Payments, Accounting Systems, Finance APIs, Inventory Management Systems, LocalStorage, User Authentication

Experience

Electricity Production Forecasting Tool

A web-based application for forecasting electricity produced by wind and solar parks in Cyprus. Some of the main functionalities of this project include the following:

• Interfaces with systems for forecasting electricity production.
• Graphical interface to advise the development of business strategies and mathematical transformations to create a final prediction.
• GraphQL API that can be used to expose predictions to other systems.

Transition Market Arrangement System

A three-tier web base application of the Cyprus Transmissions System Operator, an organization of the Electricity Authority of Cyprus. It is used to run an electricity transmission market in Cyprus.

Participants in the electricity transmission market use this system to submit their offers for buying or selling electricity. The system validates the offers against their available capacity and anticipates a matching offer from a counterparty to create a contract.

It is integrated with the organization's ERP. Once a month, it calculates relevant fees and penalties the participants must pay and commands the ERP to create relevant invoices.

Mobile Accident Care

An Android application developed using Android Studio. This application aims to help a car insurance company's employees collect all necessary information about vehicles and persons involved in an accident, including taking pictures, recording a driver's signature, and drawing an accident diagram. The accident's data is stored on an Android device. It is synchronized with a back-end system through web services and by utilizing Amazon Simple Storage Service (Amazon S3), which acts as an intermediary method for synchronizing pictures. It is now used by one of Cyprus's leading car insurance companies.

Be the Controller ++

A rebuild and redesign of the "Be the Controller" project. This project has been redeveloped to be independent of the Kinect for Windows Software Development Kit (SDK) and has been implemented in C++ programming language using only the language's standard library. The new design aims to make the project's compiling process feasible in operating systems that support C++, such as Linux. In addition, the project introduced a wrapper that wraps an unmanaged software library to a .NET-managed environment. This wrapper makes the development of Windows applications possible using the .NET framework and the project's library.

MuseumQuest

An educational adventure mobile game. This game aims to make museum visits attractive for children by offering them a fun and challenging way to learn about exhibits. This is achieved by encouraging players to perform a series of missions. The game reads a scenario, i.e., a mission's data, type, and series of tasks from an XML source, making it flexible and customizable. Therefore, the game can be used in various museums with an appropriate scenario, creating a relevant playful narrative on a historical period or theme of a museum's collection.

Be the Controller | A Kinect Tool Kit for a Video Game Control

A Be the Controller tool kit aims to help game designers quickly identify and recognize users' poses and gestures using Microsoft's Kinect motion controller. The identified poses can then be used to link these movements with actions within the game.

Education

2010 - 2011

Master of Science Degree in Computer Games Technology

City, University of London - London, United Kingdom

2001 - 2007

Bachelor's Degree in Electrical and Computer Engineering

University of Patras - Patras, Greece

Skills

Libraries/APIs

Node.js, React, REST APIs, Stripe, API Development, Stripe API, Vue, Twilio API, OpenAI API, Python API, LocalStorage, Stripe Connect API, Facebook API, Google Maps API, XNA, X (formerly Twitter) API, XGBoost, Instagram API, WinAPI

Tools

Git, NGINX, Microsoft Excel, Google Workspace, GitHub, Postman, Stripe Checkout, Google Analytics, ChatGPT, WebView, Firebase Authentication, Slack, Apache, Amazon CloudFront CDN, Jira, Plotly, Amazon CloudFront

Languages

C, C#.NET, Java, JavaScript, TypeScript, CSS, Rust, GraphQL, C++, HTML, Python, C#, PHP, SQL, HTML5, Sass, XML, Excel VBA

Frameworks

Angular, .NET, Next.js, Express.js, Selenium, AngularJS, Material UI, ASP.NET, OAuth 2, .NET Core, React Native, NestJS, Tailwind CSS, Unity3D, Windows PowerShell, Windows Presentation Foundation (WPF), LightGBM, Unity

Paradigms

Back-end Architecture, Automation, Object-oriented Programming (OOP), REST, Mobile Development, Scrum, DevOps, Agile, Microservices, Mobile App Design, Azure DevOps

Platforms

Debian Linux, Amazon Web Services (AWS), Vercel, Windows, Firebase, Android, iOS, Mobile, Linux, Twilio, DigitalOcean, Docker, OpenCart, Amazon EC2, Windows Desktop, Oracle, Azure, Blockchain, AWS Lambda

Storage

MySQL, PostgreSQL, MongoDB, JSON, Amazon S3 (AWS S3), Databases, XML Parsing, Data Integration, API Databases, NoSQL, Database Migration, Database Architecture, SQL Server 2017, Google Cloud, Cloud Firestore

Industry Expertise

Web Design, Project Management, Trading Systems

Other

Software Development, Amazon Glacier, Web Applications, Full-stack, APIs, Architecture, Web Scraping, API Integration, CRM APIs, Customer Relationship Management (CRM), QR Codes, Web Development, Websites, Software Architecture, Data Scraping, Back-end Development, Back-end, MVP Design, Proof of Concept (POC), CSV, PDF, Scraping, Software Integration, User Experience (UX), Open Source, Integration, Website Data Scraping, Full-stack Development, Bots, Algorithms, Code Review, System Architecture, Leadership, Front-end, Trading Bots, API Design, ERD, Web Crawlers, CTO, Fintech, Minimum Viable Product (MVP), Software Design, Technical Leadership, cURL, API Testing, Email Automation, Headless CMS, Document Parsing, Digital Payments, Excel Macros, Payment APIs, User Authentication, Low Code, Deployment, Game Development, Microsoft Certified Solutions Developer .NET 4.5 Web Applications Developer, Mobile Apps, Mobile App Development, DevOps Engineer, Data Cleaning, Data Organization, Web UX, Single Sign-on (SSO), ESLint, Process Automation, Computer Vision, Optical Character Recognition (OCR), Data Structures, CI/CD Pipelines, Analytical Dashboards, User Interface (UI), Natural Language Processing (NLP), Machine Learning, SaaS, Data Analysis, Automated Data Flows, Artificial Intelligence (AI), ChatGPT API, Data Science, Mobile Applications, Chatbots, Data Analytics, Concurrency, Scalable Architectures, Backtesting Trading Strategies, Technical Writing, Algorithmic Trading, Decentralized Systems, Networking, Image Recognition, eCommerce, OpenAI, Trading, Large Language Models (LLMs), IT Security, Maps, Financial Reporting Dashboards, Stripe reporting, Data Engineering, Data Visualization, Containerization, Automated Trading Software, Email Parsing, Commerce, OAuth, Design, Data Enrichment, Datasets, AI Automation, Accounting Systems, Finance APIs, Purchase Orders, Inventory Management Systems, AI Agents, Front-end Development, Prompt Engineering, SMS, Security, Meta Ads, Active Directory (AD), Windows Desktop Software, WebSockets, Accessibility, Cloudflare, Data Entry, Feature Engineering, Data Preprocessing, Social Media Integration, Augmented Reality (AR), POS, Excel 365, Reinforcement Learning

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