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Marko Pađen, Software Developer in Berlin, Germany
Marko Pađen

Software Developer in Berlin, Germany

Member since August 13, 2019
Marko has over a decade of experience with large-scale software including architecture, design, coding, testing, documentation, build, and release. He's held a variety of roles throughout his career such as software engineer and architect, technology lead, full-stack developer, scrum master, QA mentor, and DevOps engineer.
Marko is now available for hire
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Portfolio

Experience

Location

Berlin, Germany

Availability

Full-time

Preferred Environment

Amazon Web Services (AWS), AWS, DevOps, Azure, .NET Core

The most amazing...

...design and implementation I did was critical parts of DNS ENUM server with UDP load balancer. It's auto-scalable in containerized environment and low latency.

Employment

  • Senior .NET Full-stack Developer

    2021 - 2022
    Communauto, Inc
    • Implemented and tested modern security patterns for legacy applications.
    • Upgraded front-end frameworks to the latest version with many braking changes.
    • Tested the entire IT system for security vulnerabilities, including web and REST.
    Technologies: .NET, .NET Core, ASP, ASP.NET Core, ASP.NET MVC, REST, SQL, SQL Server 2015, Bootstrap 3+, NPM, jQuery, JavaScript, TypeScript, HTML, CSS, Web Security

  • Senior Back-end Developer

    2020 - 2021
    Leading Content SaaS Company
    • Developed API integrations with official regulators worldwide.
    • Developed event-based fast data processing services.
    • Worked on improving code quality by centralizing and organizing documentation and standards.
    Technologies: .NET, C#, Azure, Azure Table Storage, Azure DevOps, TeamCity, NuGet, Angular, Azure Service Bus, REST, API Integration

  • Senior Full-stack Developer

    2020 - 2020
    Gemini Diversified Services
    • Worked on new and existing features in client-facing Angular application on front-end and back-end (REST MVC Web API).
    • Developed new features for the back-office portal in .Net MVC with Entity Framework over Azure SQL database.
    • Implemented CI/CD with SonarCloud static code analysis, gated pull request, and automated policy-based deployment in Azure DevOps.
    • Maintained and improved multiple Azure deployments including orchestrated deployments, network, and security.
    Technologies: SQL, Azure, Angular, .NET

  • Lead Developer

    2019 - 2020
    Online Coaching Portal
    • Managed and led a team of four developers working on an online coaching platform.
    • Worked as front-end, back-end developer, and DevOps. Implemented Twilio WebRTC and Stripe Connect integrations as well as SignalR chat and notification system.
    • Developed CI/CD with continuous testing and disposable Azure environments.
    Technologies: .NET, ASP.NET, REST, SignalR, Vue, Twilio Programmable Video, Twilio API, Azure, Azure SQL, Azure DevOps, Azure Resource Manager (ARM), Stripe Connect

  • .NET/Angular Developer

    2019 - 2020
    Most Investments, LLC Pantheon Software
    • Worked on ASP.NET core REST API, backed with Entity Framework and Microsoft SQL Server.
    • Worked on Angular front end with Bootstrap and SurveyJS controls.
    • Implemented functional JMeter testing for REST API.
    • Implemented Jasmine/Karma UI tests.
    • Improved Docker setup.
    Technologies: Amazon Web Services (AWS), AWS, Docker, Microsoft SQL Server, SurveyJS, ASP.NET Core, Entity Framework Core, Angular, C#, .NET

  • Technology Team Lead - External

    2019 - 2019
    Roche
    • Worked as the tech lead for a project that had Angular in the front end and .NET Core in the back end.
    • Developed custom control to fit our current project, and also worked on architectural tasks like HTTP client mocking, build-time configuration, code coverage CI integration, and similar.
    • Developed REST API with all the best practices, large file uploads, Azure hosting, and so on.
    • Set up CI/CD and Terraform Azure environment creation.
    Technologies: Terraform, Azure DevOps, Azure Blob Storage API, Azure Stream Analytics, Azure Event Hubs, Azure, Azure Cosmos DB, Web API, Jasmine, Angular, C#, .NET Core, .NET

  • Head of Software Development

    2018 - 2019
    Mitto
    • Collaborated with team members on technically and domain challenging tasks.
    • Led conversations with the team regarding technology usages and improvements.
    • Set up CI/CD according to our internal process. This included release management, testing, development, disposable environments, and nightly builds.
    • Developed custom DNS UDP ENUM load balancer used in auto-scalable environments in the cloud.
    • Developed custom Prometheus integrations that work well on auto-scalable environments.
    Technologies: Amazon Web Services (AWS), PostSharp, jQuery, Kendo UI, Git, TFS, Windows PowerShell, NUnit, Selenium, SoapUI, Apache JMeter, Azure, AWS, RabbitMQ, Redis, Elasticsearch, MySQL, .NET Core

  • Senior Software Engineer

    2015 - 2018
    Mitto
    • Acted as the full-stack developer on https://www.nimbow.com/. Made some interesting features, like auto-extraction of uploaded Excel files of any structure.
    • Served as the technology lead on Number Lookup Services. Developed a performant lookup system.
    • Designed system improvements to migrate from the data center. In the cloud, we achieved 2,000/s requests served with less than <100ms. The pure time of our system was <20ms, the rest of 80ms was an external dependency.
    • Introduced AOP practices based on static proxy and IL weaving to solve problems like DB connection pool management (cluster-ready), generic caching, RPC calls.
    Technologies: Amazon Web Services (AWS), PostSharp, jQuery, Kendo UI, Git, TFS, Windows PowerShell, NUnit, Azure, AWS, RabbitMQ, Redis, Elasticsearch, MySQL, .NET Core

  • Senior Software Developer

    2012 - 2015
    IGT
    • Contributed to full-stack development and testing betting software. Developed an interesting MVVM-based event-driven model for betting views - performant on rendering multiple views on multiple screens.
    • Mentored team members on new technologies, like WPF, Postsharp, and similar.
    • Presented new technologies in-house during development technology stack improvement program. Had a task of presenting WPF with all the benefits it gets on our use cases.
    • Mentored 2nd level support and provided them assistance on remote administration tools developed in-house.
    • Developed generic tools for using various POS devices in betting.
    Technologies: Keyboards, POS, SoapUI, Apache JMeter, TFS, TeamCity, NAnt, Oracle Coherence, Oracle Database, DB, Oracle, Windows Presentation Foundation (WPF), ASP.NET, .NET

  • Software Developer

    2011 - 2012
    IT Excellence
    • Created custom Kendo UI-based application that imports Excel with Pivot table and creates proper OLAP cubes used later for ETL processes.
    • Developed web and Windows Phone part of the application that is a social network for public issues.
    Technologies: Windows Phone, Windows Communication Framework (WCF), jQuery, Kendo UI, HTML, MDX, Microsoft SQL Server, MS Silverlight, ASP.NET, .NET

  • Software Developer

    2011 - 2012
    Best Solution Team
    • Developed custom HTML-based controls for ASP.NET (like flex-grid, control alignment helpers).
    • Developed MS Office plugins which integrate with our web portal.
    • Integrated ActiveX TWAIN controls into our portal.
    • Automated MS Office processes with ClosedXML framework.
    Technologies: Plugins, Entity Framework, Microsoft SQL Server, ASP.NET

  • Software Developer

    2010 - 2011
    LMG Group
    • Made XML-based configurable white label web site for selling mobile content (Java games, MIDI ringtones, images, videos).
    • Integrated phone model database with auto-detecting features.
    • Integrated with mobile providers in a secure way. Handled payments.
    Technologies: Microsoft SQL Server, ASP.NET

  • Software Engineer

    2007 - 2010
    PR Padjen
    • Developed custom TCP/IP application protocol for live distributed ERP work.
    • Made imports from many popular small ERP systems used locally (MS SQL, IMB db2, FoxPro).
    • Made distributed licensing mechanism with payment portal with admin access.
    Technologies: MS Silverlight, ASP.NET, Microsoft Access, Microsoft SQL Server, TCP/IP, VB.NET

Experience

  • Imperfect Dollop
    https://github.com/notmarkopadjen/imperfect-dollop

    A .NET library that helps the user create distributed in-memory cache.
    Useful for serving not-so-time-sensitive data to many clients. It has all the benefits of the in-memory cache with added distributed synchronization.

  • Azure DevOps Workflow
    https://marketplace.visualstudio.com/items?itemName=mitto-ag.workflow

    Designed workflow for Scrum process in Mitto AG.

    Contributed to development.

  • Redis Insights

    Developed open-source software while employed at Mitto AG.

  • CodinGame Member
    https://www.codingame.com/profile/7d385fb020073138ae675a9b4c82a42e5463662

    Part of challenging algorithm problem-solving community.

    ID: not_marko_padjen

  • Number Lookup

    Technology/team lead.

  • Nimbow
    https://www.nimbow.com/

    Enterprise SMS sending portal.

    Full-stack developer, part of a larger team.

  • Sports Betting

    Full-stack developer, part of a larger team.

  • Caching and Connection Handling in .NET: An Aspect-Oriented Programming Tutorial (Publication)
    https://www.toptal.com/dot-net/aspect-oriented-programming-tutorial
    We reduce boilerplate with common OOP patterns, but often, the code overhead of using patterns is almost the same—if not bigger—than if we’d used boilerplate code in the first place. In aspect-oriented programming tutorial, we implement two functions (aspects) that allow for generic database connection management and caching. These allow us to mark methods that, when called, will automatically have the required functionally present in through IL weaving.

Skills

  • Languages

    Java, C#, SQL, HTML, HTML5, VB.NET, JavaScript, TypeScript, CSS, UML, MDX, Go

  • Frameworks

    ASP.NET Web API, .NET, .NET Core, NUnit, Blazor, SpecFlow, ServiceStack, ASP.NET, ASP.NET Core 2, ASP.NET MVC, ASP.NET Core MVC, Kendo UI, Kendo UI MVVM, Selenium, Angular, Windows Presentation Foundation (WPF), Bootstrap, Windows Communication Framework (WCF), Jasmine, Entity Framework Core, ASP.NET Core, AWS HA, Ext JS, Windows PowerShell, Cypress.io, ASP, Bootstrap 3+

  • Libraries/APIs

    Entity Framework, WinForms, REST APIs, Vue, Web API, Azure Blob Storage API, SurveyJS, jQuery, XNA, SignalR, Twilio API, Stripe Connect

  • Tools

    xUnit, Microsoft Unit Tests, TFS, Git, Apache JMeter, NAnt, PostSharp, RabbitMQ, SoapUI, Keyboards, MS Silverlight, Microsoft Access, Terraform, Oracle Coherence, TeamCity, ActiveMQ, NuGet, Twilio Programmable Video, Jira, NPM

  • Paradigms

    Azure DevOps, Object-oriented Design (OOD), Microservices Architecture, Load Testing, Design Patterns, Agile, Test Automation, Object-oriented Programming (OOP), Scrum, AOP, Dependency Injection, Microservices, REST, DevOps

  • Storage

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

  • Other

    Visual Studio Team Services (VSTS), Release Management, APIs, Galera Cluster, WCF Web Services, IT Recruitment, Web Applications, Team Leadership, Containerization, Network Protocols, IoC, Orchestration, Office Plugins, Algorithms, Patterns, Cloud, Azure Stream Analytics, AWS, Plugins, TCP/IP, DevExpress, POS, Azure Service Bus, API Integration, Azure Resource Manager (ARM), SQL Server 2015, Web Security

  • Platforms

    Amazon Web Services (AWS), Docker, Azure, Azure PaaS, iOS, Azure Event Hubs, Oracle Database, Windows Phone, Oracle

Education

  • Master of Science Degree in Informational Systems and Technologies
    2011 - 2012
    Faculty of Organizational Sciences - Belgrade, Serbia
  • Bachelor of Science Degree in Informational Systems and Technologies
    2003 - 2011
    The Faculty of Organizational Sciences - Belgrade, Serbia

Certifications

  • Professional Scrum Master I
    NOVEMBER 2017 - PRESENT
    Scrum.org
  • Elasticsearch Developer I
    FEBRUARY 2017 - PRESENT
    Elastic
  • Galera Cluster for MySQL and MariaDB training
    FEBRUARY 2016 - PRESENT
    FromDual
  • Microsoft Certified Solutions Developer - Windows Store Apps Using C#
    JANUARY 2014 - JANUARY 2016
    Microsoft
  • Microsoft Specialist - Programming in C# Specialist
    DECEMBER 2013 - PRESENT
    Microsoft
  • Microsoft Certified Professional
    DECEMBER 2013 - PRESENT
    Microsoft

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