Ernestas Romeika, Developer in Saint Julian's, Malta
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Ernestas Romeika

Verified Expert  in Engineering

Software Developer

Saint Julian's, Malta
Toptal Member Since
March 1, 2017

Ernestas has over ten years of experience working with .NET-based applications. He graduated five years ago with a bachelor's degree in software engineering. He's primarily been working on web-related projects in both the front and back end. Ernestas is always up for a new challenge.


BioReference & Genedx/Sema4
C#, SQL, .NET, Postman
C#, .NET, .NET Core, Entity Framework Core, Azure Service Bus
Equiniti (Contract)
Identity Server, Redis, Entity Framework Core, GraphQL, RabbitMQ, .NET




Preferred Environment

Git, ReSharper, Visual Studio Code (VS Code), Visual Studio 2022, Windows 11

The most amazing...

...thing I've built is a machine learning-based desktop tool for sorting and categorizing files and folders.

Work Experience

C# Senior Software Engineer

2022 - 2023
BioReference & Genedx/Sema4
  • Maintained Iguana WCF server for transporting HL7 data from laboratories to healthcare providers.
  • Designed and developed REST-based communications between the main application and a laboratory information management system (LIMS).
  • Utilized MuleSoft's Anypoint system for system monitoring and API documentation.
  • Updated and optimized existing SQL stored procedures.
  • Created and executed database migration scripts (SQL) and performed deployments for UI (Angular) servers (Linux), back-end systems (C#), administrative tools (C#), and cron job services (C#).
Technologies: C#, SQL, .NET, Postman

Senior .NET Developer

2020 - 2021
  • Led the effort to migrate the legacy codebase to .NET core.
  • Participated in migrating the legacy plain JavaScript and HTML pages to Angular views.
  • Developed an image processing process and integrated it with other CAT services.
Technologies: C#, .NET, .NET Core, Entity Framework Core, Azure Service Bus

Senior .NET Engineer | Architect

2019 - 2020
Equiniti (Contract)
  • Built a web application to help the company with asset reunification, locating lost share and stock owners and their relatives, using .NET.
  • Integrated the app with the existing company tools.
  • Traveled to the US to set up local development environments and learn about the on-site team and their business model.
  • Handled the implementation of complex accounting calculations.
  • Implemented GraphQL endpoints for all requests to provide flexible front-end development.
Technologies: Identity Server, Redis, Entity Framework Core, GraphQL, RabbitMQ, .NET

.NET Software Engineer

2018 - 2019
Blackboard (via Toptal)
  • Developed the new microservices for various back-end needs and supported existing microservices.
  • Implemented and supported Postman tests.
  • Supported and implemented unit tests with MOQ.
  • Maintained the Jenkins deployment scripts.
  • Implemented and supported messaging between microservices via Azure Service Bus and Azure Event Hub.
  • Generated and validated cryptographic keys, assigning them to a specific application and storing and retrieving them from the Azure Key Vault.
Technologies: Postman, Swagger, Artifactory, Jenkins, Octopus Deploy, Microservices, Moq, Blob Storage, Azure Table Storage, Azure Cosmos DB, Azure Key Vault, Azure Event Hubs, Azure Service Bus, .NET Core

Front-end Angular Developer

2017 - 2018
South African Tourism (via Toptal)
  • Developed the front end features for the South African Tourism portal.
  • Created a real-time weather component that tracked different regions in South Africa.
  • Implemented a flexible and scalable UI design to support over 30 different languages.
Technologies: TypeScript, SCSS, Webpack, RxJS, Redux, Angular

.NET Software Engineer

2016 - 2017
  • Upgraded the architecture of the project.
  • Handled the decoupling of legacy code dependencies.
  • Moved project towards a microservice-based approach.
  • Introduced end-to-end testing and unit testing to the project.
  • Improved existing data flows.
  • Introduced data backups.
  • Refactored front-end JavaScript files to TypeScript.
  • Introduced Entity framework code-first migrations.
  • Handled deployment procedures (Jenkins configs, MSBuild tasks).
  • Monitored overall production environment stability (Dynatrace).
Technologies: Dynatrace, Gulp, Jenkins, PhantomJS, Selenium, Entity Framework, Microsoft SQL Server, TypeScript, AngularJS, Web API, .NET

.NET Software Engineer

2015 - 2016
Baltic Amadeus
  • Operated in an agile environment within a team of twelve people to create an accounting system for the Swedish market and legal system.
  • Developed a solo project for a restaurant food ordering system.
  • Integrated communications between POS machines, databases, and web services.
Technologies: Entity Framework, Microsoft SQL Server, AngularJS, Windows Communication Foundation (WCF), ASP.NET MVC, .NET

.NET Developer | Co-founder

2013 - 2015
  • Operated in an agile team environment.
  • Developed a scalable internal system for a car insurance company.
  • Built a smartphone app for a well-known Swedish photo crowdsourcing startup.
  • Supported a native Windows 8 application that manages MS Office templates.
  • Contributed to the development of an internal proprietary core codebase.
  • Deployed the .NET Azure applications, Azure Blob storage, MS SQL, and RavenDB instances.
Technologies: Orchard, Azure, RavenDB, Web API, ASP.NET MVC, .NET

.NET Developer

2012 - 2013
  • Supported a mobile web application intended for pharmacy agents.
Technologies: ASP.NET MVC, .NET

Web Developer (Intern)

2012 - 2012
Net Frequency
  • Assisted with team tasks, gaining experience, and learning the ins and outs of the industry.
Technologies: JavaScript, CSS, HTML, MySQL, Apache, PHP

Web Developer

2011 - 2012
  • Worked on various short-term web projects and applications.
Technologies: Zend Framework, PHP, ASP.NET MVC, .NET

Junior .NET Developer

2009 - 2009
  • Worked on a finance management system.
Technologies: Windows Presentation Foundation (WPF)

Incremental Randomized Delaunay Triangluation

Back in 2013, while I was doing my bachelor studies, I somehow talked my way into the university office letting me take a masters-level course on computational geometry. This was my final project for that course. I implemented incremental randomized Delaunay triangulation in optimal complexity, which was a bit tricky. You can see explanation (in Lithuanian), diagrams, and code on the link I've shared.
2011 - 2015

Bachelor's Degree in Software Engineering

Kaunas University Of Technology - Lithuania


Entity Framework, Azure Blob Storage API, jQuery, Web API, PhantomJS, RxJS, Moq


Jenkins, Gulp, NPM, Bower, Visual Studio 2019, ReSharper, Git, Dynatrace, Apache, Webpack, Azure Key Vault, Artifactory, Postman, RabbitMQ


.NET Core, Angular, AngularJS, Entity, .NET, Bootstrap, ASP.NET MVC, OAuth 2, Selenium, Orchard, Windows Presentation Foundation (WPF), Zend Framework, Redux, Swagger, Entity Framework Core, Scaled Agile Framework (SAFe)


Microsoft SQL Server, Azure Cosmos DB, MySQL, Azure Table Storage, Redis, RavenDB


C#, JavaScript, TypeScript 2, GraphQL, TypeScript, PHP, HTML, CSS, SCSS, SQL


Agile, Kanban, Microservices, Microservices Architecture


Azure Service Fabric, Windows, Azure, Azure Event Hubs, Visual Studio Code (VS Code)


Windows 10, Windows Communication Foundation (WCF), Azure Service Bus, Blob Storage, Octopus Deploy, Identity Server, Visual Studio 2022, Windows 11

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