Senior Software Engineer C#
Confirmed on the employer's own hiring board on Oct 24, 2026. First seen by Alion on Mar 9, 2026. Q-Tech scores B on the Alion truth index.
Senior Backend Engineer - .NET / Azure | Fintech B2B
At Q-tech, we’re partnering with a well-established fintech company that develops advanced banking-connectivity and cash-management solutions for large enterprises and financial institutions across more than 15 countries. We are currently looking for a Senior Backend Engineer with a strong ownership mindset to drive the evolution of their core platform.
The product is B2B, highly critical, fully audited, and directly connected to international banks. They are looking for someone who combines solid .NET backend expertise with real-world experience in Azure, DevOps, and Infrastructure as Code, and who is comfortable working in hybrid environments (cloud + on-prem infrastructures for banking clients).
What you’ll do
Design and implement backend services in C# / .NET (ASP.NETCore) with a focus on reliability, scalability, and best engineering practices.
Define versioned and stable APIs followingschema-first models to ensure long-term compatibility and traceability.
Design and maintaindata models, audit models, and key event-driven flows for reporting and regulatory compliance.
Apply critical backend patterns and engineering standards.
Contribute to distributed systems with asynchronous processing and messaging.
Work closely withDevOps to ensure consistent and reproducible environments.
Participate in the design and maintenance ofAzure infrastructure usingInfrastructure as Code.
Provide L3 support for on-prem banking environments (root-cause analysis, hotfixes, reproducibility).
Optimize SQL performance, diagnose queries, read execution plans, and propose performance improvements.
Collaborate closely withQA, Security, DevOps, and Data teams to ensure a robust and auditable product.
What they’re looking for
7+ years of experience as a Backend Engineer.
Deep expertise inC#/.NET, SQL, and distributed architectures.
Solid hands-on experience withMicrosoft Azure and IaC in production (mandatory).
Background in regulated, audited, compliance-driven or banking environments.
Hands-on experience withDocker, performance tuning, and advanced troubleshooting.
Strong ownership mindset and ability to lead technically without a people-management role.
Comfortable working in hybridcloud/on-prem environments.
High level of English is essential.
Nice to have
Previous experience in fintech, payments, treasury systems, or banking connectivity.
TDD / contract testing at scale.
Experience with messaging/queueing systems (Azure Service Bus, RabbitMQ, Kafka).
Familiarity withAzure Functions and serverless architectures.
Experience inSaaS B2B or high-throughput platforms.
Tech stack
C# / .NET (ASP.NETCore), SQL, Azure, IaC, Docker, Azure Functions, Azure Service Bus, messaging patterns, distributed systems, monitoring & observability.
What’s offered
Permanent contract.
Salary: €60,000 - €75,000, depending on experience.
Hybrid model (1/2 days) in Barcelona: flexibility + modern office.
Mission-critical B2B product with real impact on major corporations and international banks.
Senior, high-standards engineering team with a strong culture of best practices.
Stable environment with a solid roadmap and architectural responsibilities from day one.verano, y ofrecemos seguro médico.