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Software engineer with commercial experience building high-performance APIs using .NET and AWS infrastructure (Lambda, ECS, API Gateway). Focused on clean architecture, minimal APIs, production database optimization, and integrating modern AI tooling (MCP). Experienced delivering scalable microservices solutions with secure authentication/authorization flows (IdentityServer), strong CI/CD practices (Jenkins), and high code quality through unit/component/integration testing. Works with C#, ASP.NET Core Web APIs, Entity Framework Core, and SQL Server; also supports frontend development using Angular and TypeScript.…Software engineer with commercial experience building high-performance APIs using .NET and AWS infrastructure (Lambda, ECS, API Gateway). Focused on clean architecture, minimal APIs, production database optimization, and integrating modern AI tooling (MCP). Experienced delivering scalable microservices solutions with secure authentication/authorization flows (IdentityServer), strong CI/CD practices (Jenkins), and high code quality through unit/component/integration testing. Works with C#, ASP.NET Core Web APIs, Entity Framework Core, and SQL Server; also supports frontend development using Angular and TypeScript.

Daniel Szmelter

Software Engineer, Back-End Developer, Full Stack Developer, +2

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Software engineer with commercial experience building high-performance APIs using .NET and AWS infrastructure (Lambda, ECS, API Gateway). Focused on clean architecture, minimal APIs, production database optimization, and integrating modern AI tooling (MCP). Experienced delivering scalable microservices solutions with secure authentication/authorization flows (IdentityServer), strong CI/CD practices (Jenkins), and high code quality through unit/component/integration testing. Works with C#, ASP.NET Core Web APIs, Entity Framework Core, and SQL Server; also supports frontend development using Angular and TypeScript.…Software engineer with commercial experience building high-performance APIs using .NET and AWS infrastructure (Lambda, ECS, API Gateway). Focused on clean architecture, minimal APIs, production database optimization, and integrating modern AI tooling (MCP). Experienced delivering scalable microservices solutions with secure authentication/authorization flows (IdentityServer), strong CI/CD practices (Jenkins), and high code quality through unit/component/integration testing. Works with C#, ASP.NET Core Web APIs, Entity Framework Core, and SQL Server; also supports frontend development using Angular and TypeScript.

Available to hire

Software engineer with commercial experience building high-performance APIs using .NET and AWS infrastructure (Lambda, ECS, API Gateway). Focused on clean architecture, minimal APIs, production database optimization, and integrating modern AI tooling (MCP).

Experienced delivering scalable microservices solutions with secure authentication/authorization flows (IdentityServer), strong CI/CD practices (Jenkins), and high code quality through unit/component/integration testing. Works with C#, ASP.NET Core Web APIs, Entity Framework Core, and SQL Server; also supports frontend development using Angular and TypeScript.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Language

Polish

Fluent

English

Advanced

Work Experience

Junior .NET Developer at DTiQ

May 1, 2026 - Present

Designed and implemented REST APIs within a microservices architecture using .NET (C#), Minimal APIs, and Entity Framework Core following Clean Architecture and Vertical Slice patterns. Developed business-critical endpoints including credential recovery workflows, location data access, and hardware specification services. Built public API services acting as a proxy layer and centralized authentication, authorization, and access control across microservices; integrated IdentityServer for secure auth flows. Delivered scalable and secure solutions using AWS (API Gateway, Lambda, ALB, ECS, Parameter Store, ElastiCache, CloudWatch, CloudFormation). Improved system reliability by addressing production issues such as query optimization and batching strategies to overcome database limitations. Implemented and enhanced AI-assisted MCP tooling (including refactoring/enhancing MCP server architecture) and refactored components, including migrations from deprecated services to new APIs (e.g., perm

Junior .NET Developer at Hello Digital World student internship agreement

October 1, 2025 - December 31, 2025

Improved performance of object validation and reduced unnecessary computations in backend services. Refactored and systematized an existing codebase to improve readability, maintainability, and scalability. Manually tested and debugged all API endpoints, reporting issues and suggesting fixes to the development team. Used Git for version control including feature branches, merge conflict handling, and pull requests. Collaborated on REST API development in ASP.NET Core ensuring consistent structure, validation, and error handling.

Junior IT Specialist at Euromedia Comunicación 2-week international internship (Erasmus+ project)

October 1, 2023 - October 31, 2023

Parametrized SQL queries using PHP. Migrated articles/news from the old website to the new one using the WordPress content management system. Standardized virtual business profiles using WordPress content management systems.

Junior IT Specialist at Mondi Świecie S.A.

July 1, 2023 - August 31, 2023

Developed and improved software according to established requirements and best programming practices (ASP.NET Core MVC application). Ensured high-quality code and promoted appropriate coding methodologies. Designed application architecture and prepared project documentation. Created reports using Microsoft Excel.