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Serafeim MakrisSM

Serafeim Makris

Senior .NET Architect | Legacy Code Modernization

€600/day
Brussels, BE
8-15 years

Average response time: 1 hour

About Serafeim

I’m a Senior Software Architect with over 10 years of experience designing and modernizing enterprise applications built on .NET.

My background also includes PKI, eIDAS, and digital signature services, enabling secure and compliant solutions across regulated environments.

I specialize in legacy-to-latest migrations — upgrading .NET Framework codebases to modern .NET, introducing clean architecture principles, and applying design patterns that make software more robust and maintainable.

I collaborate closely with clients to analyze existing solutions, define realistic modernization strategies, and improve system reliability while reducing technical debt.

Always open to meaningful collaborations — let’s connect
  • Greek

    Native or bilingual

  • English

    Fluent

  • French

    Basic

Remote only
Primarily works remotely

Experience

  • TELMACO
    DG-SCIC Administrative and support service activities
    TELECOMMUNICATIONS
    November 2024 - Today (1 year and 7 months)
    Brussels, Belgium
    • Manage administrative and support service activities
    • Operate technical elements within the conference space
    • Ensure smooth running of events
    • Responsible for technical setup, operation and maintenance of conference facilities
    • Troubleshoot technical issues
    • Communicate with teams and clients for successful execution of conferences
    • Focus on security, specifically authentication and authorization systems development
    • Stay updated with latest technological advancements
    • Implement new technologies to improve services and operations
    • Enhance skills and knowledge to meet evolving client needs.
    C# External API integration sound engineering Audiovisual sector Video production
  • Adacom S.A.
    Senior Software Engineer / PKI Solution Architect
    TECH
    May 2019 - November 2024 (5 years and 5 months)
    Athens, Greece
    • Defined the company's roadmap in collaboration with the Management Team.
    • Used Agile processes to deliver easily measurable results.
    • Worked closely with colleagues in Frontend, DevOps, PKI, Product, and Support to foster a collaborative working environment.
    • Mentored and coached colleagues to ensure knowledge distribution.
    • Converted the needs of other companies (such as Gov, Banks) into solutions.
    • Architected the PKI RestAPI infrastructure and also digital signatures and eID.
    • Implemented Connectors for most popular PKI Vendors in Europe (Symantec, Entrust, Docusign, Ascertia, etc.).
    • Drove operational improvements that resulted in savings and improved profit margins.
    • Implemented RestAPIs such as CSC, OpenID Connect, and OAuth2 to expand the company project at Global standards.
    • Used technologies such as DotNet Core (3.1 and 9), DotNet Framework 4.7, Java, SpringBoot, Javascript, SQL, MSSQL, NoSQL, and Microservices.
    • Acted as a Software Architect and Senior Software Engineer.
    C# Digital Signature software architect SQL Back-End development
  • Intale
    Full stack Developer
    TECH
    April 2018 - May 2019 (1 year and 2 months)
    Athens, Greece
    • Contributed ideas and suggestions in team meetings and delivered updates on deadlines, designs and enhancements.
    • Reviewed code, debugged problems and corrected issues.
    • Continuous communication with team leaders and managers regarding any arising retail issue and discussions on new assignments or projects.
    • Constant contact with support team to arising customer issues.
    • Leader of a small backend team (consisting of 3 people).
    • Cooperation with DBA and sys admins to redesign all of the backend flows and logic's.
    • Optimizing Tiers, VMs and databases in azure to preserve the company's budget for 30k in costs per month. Technologies (C#, DotNet Core (2.1), DotNet Framework 4.7, php, JavaScript, Node.js, Azure, SQL, MSSQL, NoSQL).
    C# Node.js PHP Microsoft Azure Database Management (e.g., SQL, NoSQL)

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Education

  • BACHELOR'S DEGREE - COMPUTER SCIENCE AND TELECOMMUNICATIONS
    Technological Educational Institute of Thessaly
    2022
    BACHELOR'S DEGREE - COMPUTER SCIENCE AND TELECOMMUNICATIONS

Skill set

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