Senior .NET Developer / Tech Lead

Project/Client: Fintech Location: Lithuania Start Date: ASAP Duration: 12 months Language: English

Role Overview:

We’re looking for a Senior .NET Developer / Tech Leadto 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 designand architectural decisions
• Build integrations with REST APIs, third-party platforms, messaging, and file-based interfaces
• Ensure code quality through code reviewsand engineering best practices
• Mentor developers and lead technical discussions
• Work with SQL, relational databases,CI/CD, and Docker
• Build secure, reliable, and scalablesoftware solutions
• Collaborate with product, compliance, QA, and other engineering teams

Must-Have Requirements:

• 7+ yearsof hands-on C# / .NETexperience
• Strong backend developmentexperience
• Experience with REST APIs, integrations, and distributed systems
• Strong SQLand relational database experience
• Experience with Dockerand CI/CD
• Understanding of secure and reliable software development
• Experience as a Senior Engineer,Tech Lead, or similar
• Ability to take technical ownershipand 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 Azureor AWS

• What we offer
• Model: B2B contract with Bonapolia - one contract, one monthly invoice
• Rate: negotiated per candidate seniority and client budget
• Payment: monthly invoice, paid on the same schedule the client pays us (usually 30 days)
• Contract written under your country's law
• We handle the client-side paperwork: MSA, NDA, invoicing

🏢 About Bonapolia Bonapolia is a family-owned IT staff augmentation team based in Lisbon. We build engineering teams for product companies and IT consultancies across Europe and the US. More at http://bonapolia.com 📩 Ready to Join? We look forward to receiving your application and welcoming you to our team!