Senior .NET Developer — REST APIs, Clean Architecture & Growth

Affinity; Lisboa; On-site; EUR 60,000 - 90,000; Full time

Job summary

Affinity is a Portuguese technology consulting company with offices in Lisbon, Porto and Óbidos. We are seeking a senior developer to join our Lisbon team, focusing on C#/.NET, API design, and frontend elements.

You will work on RESTful services, data modeling, and modern web applications in a collaborative environment. The ideal candidate has 5+ years of experience in backend and API development, strong JavaScript skills, and a solid understanding of software architecture patterns.

Qualifications

• Degree in Computer Engineering or a similar field.
• 5+ years of professional experience in development with C# (.NET).
• 5+ years of experience in API design and development (Web and REST in C#).
• Strong experience in web-based development with JavaScript.
• Good knowledge of SQL and Data Modeling, from intermediate to advanced levels.
• Knowledge of design principles and architecture patterns (DDD, SOLID, Clean Architecture).
• Experience with Unit Testing and TDD.
• Affinity values teamwork, empathy, and proactive communication.
• Experience with frontend frameworks like React or Vue.js, and TypeScript, CSS, HTML is a plus.

Skills

C#/.NET

API design

JavaScript

SQL/Data modeling

DDD/SOLID/Clean Architecture

Unit Testing/TDD

React/Vue.js (bonus)

TypeScript/CSS/HTML (bonus)

Proactive mindset

Education

Degree in Computer Engineering or similar

Job description

Affinity is a Portuguese technology consulting company with offices in Lisbon, Porto and Óbidos. We are seeking a senior developer to join our Lisbon team, focusing on C#/.NET, API design, and frontend elements.

You will work on RESTful services, data modeling, and modern web applications in a collaborative environment. The ideal candidate has 5+ years of experience in backend and API development, strong JavaScript skills, and a solid understanding of software architecture patterns.