Senior Backend Engineer (.NET) in Office (Lviv)

About:
We are looking for a Senior Backend Engineer (.NET) to join a healthcare project focused on building a Connected Device Data Platform that ingests biometric data (pulse, heart rate, O2, steps, accelerometer) from smartwatch wearable devices via AWS IoT Core and delivers it to a companion mobile app.

This is a hands-on senior role requiring strong autonomy, ownership of a .NET Core codebase, and experience working with AWS cloud-native services.

This position provides the possibility of business trips (EU, USA) and occasional visits to the Lviv office when needed.

What We’re Looking For:

• 5+ years of backend development experience with .NET Core / C#


• Strong experience designing and building REST APIs with ASP.NET Core


• Solid PostgreSQL skills (data modeling, query optimization, migrations)


• Hands-on experience with AWS services: Lambda, S3, RDS, CloudWatch, SNS/SQS, Cognito


• Experience with event-driven/message-based architectures (Amazon MSK / Kafka or similar)


• Experience with microservices architecture and serverless patterns (AWS Lambda)


• Working knowledge of Docker/Kubernetes (AWS EKS)


• Experience integrating third-party notification services (Twilio, Firebase, or similar)


• Ability to read and analyze unfamiliar codebases, including Java, to understand integration points


• Good English communication skills for daily interaction with PM and cross-team coordination


• Experience working in Agile/Scrum environments (planning, backlog grooming, demos)

Your Responsibilities:

• Own and evolve the Lifeline Connect REST API (.NET Core) serving the Flutter mobile app


• Manage and extend PostgreSQL data models for patient/device data, biometric records, user management, and alarm events


• Build the alarm/notification service using AWS Lambda and Amazon MSK (Kafka), delivering notifications via Twilio and Firebase


• Develop and maintain the IoT data enrichment pipeline, processing MQTTS device data and persisting it to InfluxDB and PostgreSQL


• Integrate authentication and user management using Amazon Cognito


• Contribute to building the IoT Device Manager for registration and provisioning via AWS IoT Core


• Analyze incoming Java code deliveries from the hardware team to understand device-side logic and integration points


• Implement integrations with third-party monitoring services and healthcare providers


• Prepare the platform for AWS HealthLake (FHIR) integration


• Participate in 2–3 week sprint cycles, communicating technical decisions and assessments


• Maintain technical documentation, API specifications, and architecture documentation


• Contribute to HIPAA compliance foundations (encryption, access control, audit trails)


• Support future AI/ML-driven features (anomaly detection, predictive analytics) and new IoT device integrations

Will Be a Plus:

• Experience with healthcare platforms, biometric data processing, or HIPAA/GDPR compliance


• Familiarity with time-series databases (InfluxDB, AWS Timestream)


• Experience with Amazon Cognito or similar authentication systems (OAuth 2.0, user pools)


• Experience with FHIR standards or AWS HealthLake


• Experience integrating AI/ML services (anomaly detection, predictive analytics)