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Hi, I'm Krystian Koszucki, a Full Stack Developer with commercial experience in building scalable and efficient applications mainly using .NET and Angular. I enjoy working in cross-functional, multinational teams and following Agile (Scrum) methodologies to deliver quality solutions. I have experience developing mobile apps, admin panels, customer web apps, and APIs, and I am passionate about planning and building new features with a focus on security and performance. I love learning new technologies and improving my skills to create robust applications.…Hi, I'm Krystian Koszucki, a Full Stack Developer with commercial experience in building scalable and efficient applications mainly using .NET and Angular. I enjoy working in cross-functional, multinational teams and following Agile (Scrum) methodologies to deliver quality solutions. I have experience developing mobile apps, admin panels, customer web apps, and APIs, and I am passionate about planning and building new features with a focus on security and performance. I love learning new technologies and improving my skills to create robust applications.

Krystian Koszucki

Full Stack Developer, Developer, Programmer, +2

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Hi, I'm Krystian Koszucki, a Full Stack Developer with commercial experience in building scalable and efficient applications mainly using .NET and Angular. I enjoy working in cross-functional, multinational teams and following Agile (Scrum) methodologies to deliver quality solutions. I have experience developing mobile apps, admin panels, customer web apps, and APIs, and I am passionate about planning and building new features with a focus on security and performance. I love learning new technologies and improving my skills to create robust applications.…Hi, I'm Krystian Koszucki, a Full Stack Developer with commercial experience in building scalable and efficient applications mainly using .NET and Angular. I enjoy working in cross-functional, multinational teams and following Agile (Scrum) methodologies to deliver quality solutions. I have experience developing mobile apps, admin panels, customer web apps, and APIs, and I am passionate about planning and building new features with a focus on security and performance. I love learning new technologies and improving my skills to create robust applications.

Available to hire

Hi, I’m Krystian Koszucki, a Full Stack Developer with commercial experience in building scalable and efficient applications mainly using .NET and Angular. I enjoy working in cross-functional, multinational teams and following Agile (Scrum) methodologies to deliver quality solutions.

I have experience developing mobile apps, admin panels, customer web apps, and APIs, and I am passionate about planning and building new features with a focus on security and performance. I love learning new technologies and improving my skills to create robust applications.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Language

Polish

Fluent

English

Advanced

French

Intermediate

Work Experience

Full Stack .NET Developer at Appstronauts

October 1, 2023 - Present

Utilized .Net 5.0, .Net 4.6.2, Nancy, Angular, Ionic, SQL, Azure, and TeamCity for development. Worked simultaneously on a Mobile App for Technician’s Tracking, Admin Panel, Customer WebApp, and API. Expanded an API synchronizing two APIs. Planned and built new features including SMS Service, Reschedule Service, and Reports Service. Executed deployments and onboarded new employees assigning them sub-tasks.

.NET Developer at Freelance

May 31, 2025 - July 30, 2025

Utilized .Net 8.0 for development. Built and synchronized two APIs for managing and updating invoices.