Senior C#/.NET Backend Developer

QUANTEAM (RAINBOW PARTNERS Group); Porto; On-site; EUR 65,000 - 90,000; Full time

Benefits offered by this job

Health insurance

Extra holiday: Christmas Eve or New Y'

Access to Quanteam Academy

Elevate Program

Consultant Expert support

Job summary

Quanteam, founding entity of RAINBOW PARTNERS, is a consulting firm focused on Banking and Financial Services. We are seeking a Senior C#/.NET Backend Developer – Anti-Fraud based in Porto to design and implement backend solutions for fraud monitoring and trading controls.

The role involves modernization, data processing workflows, and secure software practices within an Agile team. The position offers a permanent CTI contract, health insurance, extra holidays, and access to Quanteam Academy for

Qualifications

• 6–9 years of backend development experience.
• Strong proficiency in C#, .NET and .NET Framework.
• Advanced SQL skills, including stored procedures and views.
• English B2 level or above, Porto-based.
• Experience with Agile and DevSecOps practices.

Responsibilities

• Develop and maintain backend applications for anti-fraud monitoring.
• Design robust, scalable solutions in C#/.NET.
• Modernize legacy systems and upgrade architectures.
• Collaborate with stakeholders in an Agile environment.

Skills

Backend development

C# / .NET

SQL & DB design

RESTful APIs

SOLID principles

Agile methods

DevSecOps

English (B2+)

Tools

SQL Server

Job description

Quanteam, founding entity of RAINBOW PARTNERS, is a consulting firm specialized in Banking and Financial Services. With more than 1200 consultants across 10 countries, we combine business and IT expertise to support leading institutions in transformation projects.

Our core areas:

Operations & Finance

We are looking for a Senior C#/.NET Backend Developer – Anti-Fraud

• Develop and maintain critical backend applications that monitor trading activities and detect potential fraud and anomalies.
• Design robust and scalable solutions using C#, .NET and .NET Framework.
• Drive application modernization, including upgrades of obsolete technologies and improvements to existing architectures.
• Develop and optimize database structures, complex stored procedures and views.
• Implement data processing workflows and business rules supporting trading controls and compliance.
• Establish automated testing frameworks to improve application reliability and prevent regressions.
• Contribute to DevSecOps practices and continuous improvements in software quality and security.
• Collaborate with business stakeholders and technical teams in an Agile environment.
• 6–9 years of relevant software development experience, with a strong focus on backend development.
• Strong proficiency in C#, .NET and .NET Framework.
• Proven experience in application architecture, modernization and technical upgrades.
• Advanced SQL skills, including database design, complex stored procedures, views and query optimization.
• Experience establishing automated testing frameworks.
• Good knowledge of RESTful APIs, SOLID principles and design patterns.
• Familiarity with DevSecOps practices and secure software development.
• Strong analytical skills and a data-oriented approach to problem-solving.
• Initiative, technical leadership and the ability to drive improvements.
• Experience working with Agile methodologies.
• English proficiency at B2 level or above.
• Position based in Porto.
• This role offers a gross annual salary, defined according to the candidate’s experience and competencies.
• Permanent contract (CTI).
• Health insurance.
• Extra holiday: Christmas Eve or New Year’s Eve.
• Access to Quanteam Academy for continuous learning and certifications.
• Elevate Program to support professional development and career growth.
• Ongoing follow-up and technical support provided by a Consultant Expert.