About Onwelo
Onwelo is a technology partner delivering end-to-end services — from strategy and architecture, through implementation, to maintenance — in the areas of digital transformation, data, and automation. The team is over 400 specialists with strong senior-level competencies and 300+ completed projects for large organizations in Poland, Europe, and the USA. Onwelo operates from several Polish cities as well as offices in Germany, Switzerland, and the USA, combining local presence with global reach.
About the project
At Onwelo we continuously grow our engineering teams and respond dynamically to our partners' needs. We are looking for .NET developers who will strengthen our projects wherever competency gaps appear or new work phases start.
By going through a single recruitment process with us, your skills are mapped to the current needs of various teams. We deliver projects for clients from industries such as automotive, healthcare, finance, and media & digital marketing, and also develop our own products. After technical verification, we match your profile to projects where your experience will bring the most value and respond to the client's real business challenges.
Your tasks
•Designing, implementing, and developing backend applications in .NET (C#) — from architecture to finished code.
•Creating and maintaining microservices and APIs (REST, gRPC) and integrating them with external systems.
•Working with databases (relational and NoSQL), ensuring query optimization and schema migrations.
•Implementing cloud solutions and using containerization (Docker, Kubernetes).
•Ensuring code quality through regular participation in code reviews, writing tests (unit, integration), and collaborating on CI/CD automation.
•Diagnosing and resolving production issues, and participating in application monitoring and maintenance.
•Optionally (depending on the project): collaborating on tasks requiring frontend support (Angular/React).
Who we are looking for
•Minimum 3 years of commercial software development experience in .NET (C#) and ASP.NET Core.
•Good knowledge of microservices architecture and design patterns used in web applications.
•Ability to efficiently use Docker and Kubernetes.
•Practical knowledge of cloud solutions — our preferred standard is AWS, but knowledge of Azure or GCP will also be an asset.
•English language proficiency at a minimum of B2 — a necessary condition for daily communication in international projects (USA/Europe).
•Knowledge of API creation/management tools (Swagger/OpenAPI) and service testing tools (e.g. Postman).
•Ability to write unit and integration tests.
•Nice to have: commercial experience or openness to working with Angular or React frameworks.
What we offer
•Flexible hours and the possibility of hybrid or remote work
•Participation in interesting projects for global clients
•As much as 80% of promotions in our company happen internally
•90% of the management staff has a technical education
•Access to internal training and development paths
•Participation in team events, company meetings, and Town Halls
•Support in building a professional image (personal branding)
•Access to life insurance and private medical care for yourself and your family
•MultiSport card, which supports health and fitness
