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I am a Senior Backend Engineer with over 15 years of experience specializing in banking, FinTech, and payment solutions. I have a strong track record of developing and maintaining large-scale systems supporting more than 500,000 POS devices, financial integrations, and high-performance APIs using .NET Core and ASP.NET. Based in Germany, I am actively seeking senior backend engineering roles within Europe's vibrant FinTech and IT ecosystem. I hold the Germany Opportunity Card and am available immediately to contribute my technical expertise and leadership in backend development. My professional journey has equipped me with comprehensive experience delivering robust solutions, automations, and integrations in challenging financial industry environments.…I am a Senior Backend Engineer with over 15 years of experience specializing in banking, FinTech, and payment solutions. I have a strong track record of developing and maintaining large-scale systems supporting more than 500,000 POS devices, financial integrations, and high-performance APIs using .NET Core and ASP.NET. Based in Germany, I am actively seeking senior backend engineering roles within Europe's vibrant FinTech and IT ecosystem. I hold the Germany Opportunity Card and am available immediately to contribute my technical expertise and leadership in backend development. My professional journey has equipped me with comprehensive experience delivering robust solutions, automations, and integrations in challenging financial industry environments.

Mehmet Yagci

Back-End Developer, Developer, Full Stack Developer, +1

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I am a Senior Backend Engineer with over 15 years of experience specializing in banking, FinTech, and payment solutions. I have a strong track record of developing and maintaining large-scale systems supporting more than 500,000 POS devices, financial integrations, and high-performance APIs using .NET Core and ASP.NET. Based in Germany, I am actively seeking senior backend engineering roles within Europe's vibrant FinTech and IT ecosystem. I hold the Germany Opportunity Card and am available immediately to contribute my technical expertise and leadership in backend development. My professional journey has equipped me with comprehensive experience delivering robust solutions, automations, and integrations in challenging financial industry environments.…I am a Senior Backend Engineer with over 15 years of experience specializing in banking, FinTech, and payment solutions. I have a strong track record of developing and maintaining large-scale systems supporting more than 500,000 POS devices, financial integrations, and high-performance APIs using .NET Core and ASP.NET. Based in Germany, I am actively seeking senior backend engineering roles within Europe's vibrant FinTech and IT ecosystem. I hold the Germany Opportunity Card and am available immediately to contribute my technical expertise and leadership in backend development. My professional journey has equipped me with comprehensive experience delivering robust solutions, automations, and integrations in challenging financial industry environments.

Available to hire

I am a Senior Backend Engineer with over 15 years of experience specializing in banking, FinTech, and payment solutions. I have a strong track record of developing and maintaining large-scale systems supporting more than 500,000 POS devices, financial integrations, and high-performance APIs using .NET Core and ASP.NET. Based in Germany, I am actively seeking senior backend engineering roles within Europe’s vibrant FinTech and IT ecosystem.

I hold the Germany Opportunity Card and am available immediately to contribute my technical expertise and leadership in backend development. My professional journey has equipped me with comprehensive experience delivering robust solutions, automations, and integrations in challenging financial industry environments.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Language

English

Advanced

Turkish

Fluent

Work Experience

Senior Backend Engineer at Wordline Turkey

May 1, 2024 - Present

Developed web modules, REST APIs, and background services for the Terminal Management System platform managing over 500K+ POS devices across Turkey. Implemented services enabling daily and monthly automated reporting of all POS transactions to the Turkish Revenue Administration.

Software & Integration Engineer at AnterraTech

May 1, 2024 - July 28, 2025

Developed financial integration solutions between Acumatica ERP and AnterraBI using AWS SQS, AWS Lambda, and C#. Resolved integration issues and delivered custom features ensuring smooth data flows. Executed critical work enabling the company to become an Acumatica partner. Consistently delivered high-quality, on-time results improving customer satisfaction and operational efficiency.

Senior Consultant & Full Stack Developer at Halkbank

September 1, 2021 - July 28, 2025

Led development and modernization of core banking applications. Built RESTful APIs and web modules using ASP.NET Core MVC 3.1, ASP.NET Core Web API, IBM Mainframe, IBM DB2, CQRS, MediatR, Elasticsearch, AutoMapper, and LINQ. Ensured code quality with SonarQube, Fortify, and custom static code analysis tools. Managed migrations of new features and bug fixes through various environments using Jenkins.

Architect & Full Stack Developer at Yesilsoft

December 31, 2020 - July 28, 2025

Architected and implemented a web-based Tire Management System for commercial fleets. Designed database schemas and data models in collaboration with Product Owner. Developed RESTful APIs supporting mobile applications on Android and iOS platforms. Utilized technologies including MVC, Web API, C#, Entity Framework, MSSQL, AutoMapper, and Elasticsearch.

Senior Backend Engineer at Wordline Turkey

May 1, 2024 - Present

Building web applications and RESTful APIs for the Terminal Management System (TMS). Developed web modules, REST APIs, and background services for managing over 500K POS devices across Turkey. Implemented daily and monthly automated reporting of all POS transactions to the Turkish Revenue Administration.

Software & Integration Engineer at AnterraTech

May 1, 2024 - July 28, 2025

Developed financial integration solutions between Acumatica ERP and AnterraBI using AWS SQS, AWS Lambda, and C#. Delivered critical work to become an Acumatica partner. Resolved integration issues and delivered custom features to ensure smooth data flows. Consistently delivered high-quality, on-time results improving customer satisfaction and operational efficiency.

Senior Consultant & Full Stack Developer at Halkbank

September 1, 2021 - July 28, 2025

Led development and modernization of core banking applications. Built RESTful APIs and web modules using ASP.NET Core MVC 3.1, Web API, IBM Mainframe, IBM DB2, CQRS, MediatR, Elasticsearch, AutoMapper, and LINQ. Ensured code quality with SonarQube, Fortify, and custom static code analysis tools. Managed migrations of new features and bug fixes across multiple environments using Jenkins.

Architect & Full Stack Developer at Yesilsoft

December 31, 2020 - July 28, 2025

Architected and implemented a web-based Tire Management System for commercial fleets. Designed database schemas and data models in collaboration with the Product Owner. Developed RESTful APIs supporting mobile applications on Android and iOS. Utilized MVC, Web API, C#, Entity Framework, MSSQL, AutoMapper, and Elasticsearch.

Senior Backend Engineer at Worldline

May 1, 2024 - Present

Developed web applications and RESTful APIs using C# and ASP.NET Framework for the Terminal Management System, managing over 500,000 POS terminals across Turkey in real time. Created C# integration services that synchronized transaction data with a 100% success rate and ensured compliance with Turkish Revenue Administration regulations.

Integration Engineer at Anterra Technology

May 1, 2024 - August 17, 2025

Engineered integration between Acumatica ERP and AnterraBI platform using the AWS serverless stack and C# enabling real-time financial data synchronization for 10+ clients. Led technical development for Acumatica ISV certification by completing over 20 compliance requirements, securing official partnership. Automated customer setup for Acumatica integrations reducing implementation time from days to minutes, significantly increasing operational efficiency.

Full Stack Developer at Halkbank

September 1, 2021 - August 17, 2025

Performed full-stack development for thousands of users on the core banking platform of Turkey's 4th largest bank. Developed RESTful services and web modules using ASP.NET Core MVC 3.1, Web API, IBM Mainframe, CQRS, and MediatR. Ensured code quality with SonarQube and Fortify and wrote unit tests using xUnit. Managed CI/CD pipelines using Jenkins across multiple environments.

Software Architect at Yesilsoft

December 31, 2020 - August 17, 2025

Architected and developed an end-to-end web-based Tire Management System for fleet operations including designing relational databases and RESTful APIs for mobile integration. Developed business logic with C# and Entity Framework and managed Agile SDLC processes leading cross-platform issue resolution.