Freelance Senior .NET Developer / Tech Lead

HITHUNTER; United States; On-site; USD 130,000 - 190,000; Full time

Job summary

HitHunter is seeking a Senior .NET Developer / Tech Lead to join our engineering team and build payment-focused backend solutions in a regulated fintech environment. The role combines hands-on development with technical leadership, designing and developing backend services and guiding architectural decisions.

You will mentor engineers, ensure code quality, and collaborate with product, compliance, QA, and other teams to deliver secure, scalable software.

Qualifications

• 7+ years of hands-on C# / .NET experience.
• Strong backend development experience.
• Experience with REST APIs, integrations, and distributed systems.
• Strong SQL and relational database experience.
• Experience with Docker and CI/CD.
• Understanding of secure and reliable software development.
• Experience as a Senior Engineer, Tech Lead, or similar.
• Ability to take technical ownership and guide other developers.

Responsibilities

• Design and develop backend services using C# / modern .NET.
• Contribute to technical design and architectural decisions.
• Build integrations with REST APIs, third-party platforms, messaging, and file-based interfaces.
• Ensure code quality through code reviews and engineering best practices.
• Mentor developers and lead technical discussions.
• Work with SQL, relational databases, CI/CD, and Docker.
• Build secure, reliable, and scalable software solutions.
• Collaborate with product, compliance, QA, and other engineering teams.

Tools

C# / .NET

REST APIs

Docker

CI/CD

Relational databases (SQL)

Technical ownership

Mentoring

Job description

Project/Client: Fintech

Location: Lithuania

Start Date: ASAP

Duration: 12 months

Language: English

Role Overview

We're looking for a Senior .NET Developer / Tech Lead to join our engineering team and build payment-focused backend solutions in a regulated fintech environment. This is a hands-on role combining software development with technical leadership. You'll design and develop backend services, contribute to technical and architectural decisions, and help the team maintain high engineering standards.

Key Responsibilities

• Design and develop backend services using C# / modern .NET
• Contribute to technical design and architectural decisions
• Build integrations with REST APIs, third-party platforms, messaging, and file-based interfaces
• Ensure code quality through code reviews and engineering best practices
• Mentor developers and lead technical discussions
• Work with SQL, relational databases, CI/CD, and Docker
• Build secure, reliable, and scalable software solutions
• Collaborate with product, compliance, QA, and other engineering teams

Must-Have Requirements

• 7+ years of hands-on C# / .NET experience
• Strong backend development experience
• Experience with REST APIs, integrations, and distributed systems
• Strong SQL and relational database experience
• Experience with Docker and CI/CD
• Understanding of secure and reliable software development
• Experience as a Senior Engineer, Tech Lead, or similar
• Ability to take technical ownership and guide other developers

Nice to Have

• Experience in payments, banking, fintech, or financial services
• Experience in a regulated / compliance-driven environment
• Knowledge of ISO 20022 / SEPA
• Understanding of clearing, settlement, or payment processing
• Experience with Azure or AWS

We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses and identifying potential inconsistencies or verification signals in application materials based on available information. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.