Senior .NET Developer

Workai creates digital products for modern cloud-based work environments integrating AI and technologies supporting employees worldwide. The team develops backend solutions, APIs, and integrations driving enterprise-class AI systems.

• Minimum 5 years of commercial experience building scalable web applications, backend services, or enterprise systems.
• Strong knowledge of .NET Framework, ASP.NET MVC, Web API 2, MS SQL, Entity Framework, REST, and OData.
• Familiarity with Azure services like Azure App Services, Azure Functions, Cosmos DB, Azure Search, Azure Service Bus, and Azure SQL.
• Good understanding of microservice architecture, API management, and cloud services in enterprise systems.
• Knowledge of Agile methodologies, DevOps practices, and modern development tools.
• Ability to apply Cloud Design Patterns.
• Experience building Enterprise SaaS applications.
• Skilled in .NET / C# and design patterns like Clean Architecture, DDD, CQRS, and Event Sourcing.
• Experience designing and implementing REST APIs and GraphQL for enterprise APIs.
• Knowledge of vector databases and semantic search techniques, e.g., Azure AI Search, in RAG systems.
• Familiarity with MCP / Model Context Protocol or similar contextual protocols and production experience with ML/AI APIs.
• Experience deploying AI API Layer solutions.
• Experience designing solutions resilient to high data volumes ensuring high availability.
• Experience building frameworks or application platforms.
• Analytical thinking, problem-solving, technical initiative leadership, and clear communication skills.
• Interest in new technologies and trends in cloud, AI, and agent systems.
• Proficiency in Polish (C1+) and English (B2+).
• Ability to work hybrid from Białystok area (minimum 3 days in office).
• Technical higher education, preferably in computer science or related fields.

Nice to have:

• Experience with vector databases and semantic search techniques in RAG systems.
• Experience with multi-tenant architecture including context separation, data isolation, and access policies in SaaS environments.
• Practical knowledge of conversational and dialog models, including fine-tuning, RLHF, and prompt engineering for LLMs, especially AI assistants.

• Utilize knowledge of cloud computing, system integration, and software development.
• Design and develop backend solutions on Microsoft Azure.
• Co-create scalable APIs, integrations, and application components supporting AI orchestration.
• Prepare production-ready solutions, from test environments to systems serving over 500,000 users daily in finance, retail, and public sectors.

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