Loading...
Loading...
Himalayas
About usHimalayas PlusCommunityTech stackEmployee benefitsTerms and conditionsPrivacy policyContact usFor job seekers
Create your profileBrowse remote jobsDiscover remote companiesJob description keyword finderRemote work adviceCareer guidesJob application trackerAI resume builderResume examples and templatesAI cover letter generatorCover letter examplesAI headshot generatorAI interview prepInterview questions and answersAI interview answer generatorAI career coachFree resume builderResume summary generatorResume bullet points generatorResume skills section generator© 2025 Himalayas. All rights reserved. Built with Untitled UI. Logos provided by Logo.dev. Voice powered by Elevenlabs Grants
Join the remote work revolution
Join over 100,000 job seekers who get tailored alerts and access to top recruiters.
@matthaiosioannidis
Senior .NET developer specializing in scalable backend systems and cloud-native APIs.
I am a senior backend engineer with extensive experience designing and implementing scalable, high-performance APIs and services using .NET Core, Java EE and Python. I have delivered production systems for payments, betting platforms and telecoms, led testing practices to maintain >90% coverage, and improved delivery through automation, containerization and CI/CD.
I collaborate closely with product, frontend, DevOps and QA, have acted as Scrum Master to accelerate releases, and hold multiple Azure and cloud-related certifications. I focus on maintainable code, measurable quality improvements, and pragmatic solutions that reduce defects and operational risk.
Sign up now and join over 100,000 remote workers who receive personalized job alerts, curated job matches, and more for free!

Sign up now and join over 100,000 remote workers who receive personalized job alerts, curated job matches, and more for free!

Work history, roles, and key accomplishments
Sitecore
Jun 2023 - Sep 2025 (2 years 3 months)
Designed and optimized .NET Core RESTful APIs backed by Azure Cosmos DB to enable scalable, high-performance data access; implemented xUnit/NSubstitute test suites to maintain >90% coverage and reduced defects by 30% through code reviews and best practices.
Intralot
Aug 2020 - Jun 2023 (2 years 10 months)
Built and maintained lottery and sports betting platforms using .NET Core, Java EE and Python; implemented Redis caching for low-latency real-time data and developed React/Redux agent apps, improving operational efficiency.
Viva Payments
Oct 2019 - Jun 2020 (8 months)
Built backend services for payments (card schemes, IBANs, bill payments) using .NET and SQL Server and implemented Refit-based REST APIs to integrate new payment schemas with comprehensive NUnit/Moq tests.
Nokia Hellas Technology Center
Jun 2016 - Oct 2019 (3 years 4 months)
Developed .NET Framework web tools and ASP.NET Web API 2 services for LTE/4G network documentation, improving publishing efficiency by 20% and aligning outputs with global Nokia standards.
Nokia Hellas Technology Center
Dec 2014 - Jun 2016 (1 year 6 months)
Supported In-Service Upgrades for LTE networks, debugging element servers and resolving production issues using Python automation and log analysis to perform root-cause investigations.
Degrees, certifications, and relevant coursework
Master's Degree, Advanced Information Systems
Master's Degree in Advanced Information Systems completed in February 2018 with a thesis on prediction of financial time series.
Bachelor's Degree, Electronic Engineering
Bachelor's Degree in Electronic Engineering completed in June 2013 with a thesis on design and implementation of telecommunication designs on FPGA chip.
Software and tools used professionally
You can contact Matthaios and 90k+ other talented remote workers on Himalayas.
Message MatthaiosAurora Green
Senior Full Stack Engineer, PayPal
Leo Young
Senior Software Engineer, aiticon GmbH
Nick Pavlidis
.NET Backend Software Engineer, BetAdvanced
Nomikos Kampourakis
Software Engineer, Ticketmaster
James Palmieri
Senior .NET Backend Developer, eBay
Isaac Hwang
Senior Software Engineer, Meta
Olga Tsoupaki
Backend Developer, SingularLogic
Vangelis Dendrinos
Senior Software Engineer, NTT Data
Laertis Tsekos
Senior Java Backend Engineer, AMCO
Josh Wright
Senior Software Engineer, Kiggla