> Markdown version of [/jobs/ext/2068885-senior-net-engineer](https://www.wearedevelopers.com/jobs/ext/2068885-senior-net-engineer). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior.Net Engineer - **Company:** Ersilia - **Location:** Madrid, Spain - **Contract:** Permanent contract - **Skills:** .NET Framework, Microsoft Windows, Amazon Web Services, C Sharp (Programming Language), Cloud Computing, Software Quality, Relational Databases, Software Debugging, PostgreSQL, .NET Framework 4, .NET Core, Backend, Docker - **Published:** August 15, 2026 - **Apply:** https://www.buscojobs.com.es/senior-net-engineer-en-madrid-ID-367446450 ## About the Role Strong experience with . NET Framework (not only .NET Core / .NET 6+). Solid understanding of relational databases and transactional systems. Ability to work with legacy or constrained systems. Experience owning systems that are business critical. Methodical approach to debugging and problem solving. Comfortable working autonomously with high ownership. Advanced level Spanish and English. Tech Stack: Language & Platform: C#, . NET Framework 4.8 Data: PostgreSQL or similar relational databases Infrastructure: Windows-based services, Docker where applicable, and cloud infrastructure on AWS or GCP. ## Description You will take ownership of a core backend system that is critical to the company and our customers.This system operates independently from our main platform and supports key business workflows under strict client and regulatory constraints.While the platform is constrained by customer requirements, there is room to improve internal structure, reliability, and tooling over time.Your responsibilities:Technical ownership of a core, isolated .NET system used in production.Maintain, extend, and stabilize an existing codebase built on .NET Framework 4.8.Ensure reliability, performance and correctness.Diagnose and resolve complex production issues.Collaboration with other engineering teams.Make pragmatic decisions balancing risk, maintainability, and business needs.Improve code quality and internal structure where possible.What we are looking for:5 years plus experience building and maintaining production systems with .NET.Strong experience with .NET Framework (not only .NET Core / .NET 6+).Solid understanding of relational databases and transactional systems.Ability to work with legacy or constrained systems.Experience owning systems that are business critical.Methodical approach to debugging and problem solving.Comfortable working autonomously with high ownership.Advanced level Spanish and English.Tech Stack:Language & Platform: C#, .NET Framework 4.8Data: PostgreSQL or similar relational databasesInfrastructure: Windows-based services, Docker where applicable, and cloud infrastructure on AWS or GCP.Location:Barcelona, Spain >along with a hybrid working model#J-*****-Ljbffr ## Related Videos - [Discover the open source trio you didn’t expect: .NET and PostgreSQL on Linux](https://www.wearedevelopers.com/videos/2042-discover-the-open-source-trio-you-didn-t-expect-net-and-postgresql-on-linux) - [Functions Triggers using Azure Event Grids in Azure Blob Storage](https://www.wearedevelopers.com/videos/47-functions-triggers-using-azure-event-grids-in-azure-blob-storage) - [Developing the Backend with Stefan Lingler, CTO at Shpock](https://www.wearedevelopers.com/videos/100360-developing-the-backend-with-stefan-lingler-cto-at-shpock) - [Docker Compose: Rediscovered](https://www.wearedevelopers.com/videos/1978-docker-compose-rediscovered) - [This Is Not Your Father's .NET](https://www.wearedevelopers.com/videos/967-this-is-not-your-father-s-net) - [Building resilient .NET applications for the modern age](https://www.wearedevelopers.com/videos/1551-building-resilient-net-applications-for-the-modern-age) ## Related Articles - [Dev Digest 120 - Apple and peers](https://www.wearedevelopers.com/magazine/455-dev-digest-120-apple-and-peers) - [How We Built a Worry-Free System That Runs for 10+ Years – And What We’d Do Again](https://www.wearedevelopers.com/magazine/751-how-we-built-a-worry-free-system-that-runs-for-10-years-and-what-we-d-do-again) - [Fully Remote Software Engineer Jobs](https://www.wearedevelopers.com/magazine/447-fully-remote-software-engineer-jobs) - [Where to Find Entry-Level Software Engineering Jobs](https://www.wearedevelopers.com/magazine/397-where-to-find-entry-level-software-engineering-jobs) - [Where To Find Software Engineering Jobs](https://www.wearedevelopers.com/magazine/396-where-to-find-software-engineering-jobs) - [Fullstack developer salary in Germany [2023]](https://www.wearedevelopers.com/magazine/197-fullstack-developer-salary-in-germany-2023)