Backend .Net Developer

TeamQuest is a rapidly growing Polish company engaged in the comprehensive HR consulting services, in particular in the recruitment of IT professionals. Our client develops IT solutions, mainly for prestigious clients in the financial and automotive sectors. Backend .Net Developer location: Wrocław, Białystok, Kraków, Warszawa, Łódź, Katowice, Poznań, Rzeszów, Lublin, Gdańsk Main Responsibilities Designing and implementing integrations with external systems (SOAP/XML and REST/JSON services), including data model mapping and partner error handling.Maintaining and developing an asynchronous data exchange mechanism (message queues, callbacks, statuses, request idempotency).Generating and updating API clients based on OpenAPI contracts provided by the client; responding to contract version changes.Building and maintaining mocks of external systems for test environments.Implementing business process logic in a BPMN engine (handlers in C#, process variables, signals) and decision rule models.Configuring environments (installation parameters, Docker, CI/CD pipeline), participating in preparing releases and hotfixes.Analyzing defects from business tests and production based on logs, quick fixes, collaborating with client analysts and testers.Documenting solutions and transferring knowledge within the team. Requirements Minimum 3-4 years of experience in a similar positionVery good knowledge of C# and .NET (ASP.NET Core, .NET 8 or newer)Practical experience with SOAP / XML integrations, REST/OpenAI integrationsAsynchronous architecture - message queues (RabbitMQ or equivalent), request-callback pattern, idempotency, persistence of exchange stateGood knowledge of databasesMapping of domain modelsDocker and CI/CDGit in gitflow modelEnglish language proficiency for reading technical documentationCommunicative, open to collaboration with client-side personnelAbility to work independently Good To Have Experience in the financial/banking industry or in projects for these industries We Offer Attractive salaryPossibility of fully remote workReal opportunity for professional developmentPossibility to genuinely influence the shape of projects 1