Senior Backend Developer (.NET) – IoT Platform

About the Position

Dołącz do j‑labs, do zespołu rozwijającego nowoczesną platformę Industrial IoT dla sektora energetycznego.

Industry

Energy

Location

Kraków (hybrid, 1x per week)

Salary

B2B: 130 – 150 PLN netto/h

Technologies

• IoT -.NET
• Docker
• Kubernetes
• Kafka

About the Project

• Join a team developing a modern Industrial IoT (IIoT) platform that supports the management of industrial devices, fleet operations, and large-scale data processing for clients in the energy, renewable energy, and industrial sectors.
• As a Senior Backend Developer, you will participate in building a cloud platform that supports thousands of IoT devices, ensuring secure telemetry data processing and integration with industrial systems.
• The project uses a microservices architecture, event-driven solutions, and a modern.NET and Kubernetes ecosystem.
• This is an excellent opportunity to develop skills in IoT, distributed systems, and the digitalization of energy infrastructure critical to business.

Technology stack:

• Backend:.NET 6/7/8, C#, ASP.NET Core, Entity Framework Core
• Databases: PostgreSQL, ScyllaDB
• Messaging: RabbitMQ, Kafka, MQTT
• Cloud & DevOps: Docker, Kubernetes, Helm, Terraform, Azure DevOps
• Security: Keycloak, OAuth2, OpenID Connect, JWT, PKI/mTLS
• Monitoring: Prometheus, Grafana, Loki
• Architecture: Microservices, Event-Driven Architecture, Multi-Tenant SaaS, Zero-Trust Security

Responsibilities

• Designing and developing scalable microservices using.NET (C#, ASP.NET Core Web API, Entity Framework Core).
• Creating and developing REST APIs for integration with external systems.
• Implementing a multi-tenant architecture with secure data separation and access control.
• Developing integration services for Industrial IoT devices and handling telemetry and configuration data.
• Working with PostgreSQL databases and NoSQL solutions.
• Using RabbitMQ and Kafka to build an event-driven architecture.
• Implementing best security practices, including OAuth2, OpenID Connect, JWT, PKI/mTLS, and identity management.
• Ensuring high-quality code through unit and integration tests, code reviews, and adherence to SOLID and Clean Code principles.
• Collaborating on containerizing applications and deployments in a Kubernetes environment.
• Developing and maintaining CI/CD processes and infrastructure as code (Terraform, Helm).
• Optimizing the performance of systems supporting thousands of devices and large data volumes.
• Collaborating with product teams, architects, and DevOps engineers.

Requirements

• Minimum of 6 years of experience in backend software development.
• Excellent knowledge of C#, .NET 6/7/8+, ASP.NET Core Web API, and Entity Framework Core.
• Experience in designing RESTful APIs.
• Practical knowledge of microservices architecture and distributed systems.
• Production experience with PostgreSQL, including schema design, query optimization, and Entity Framework Core.
• Knowledge of queuing systems and asynchronous communication (RabbitMQ or Kafka).
• Experience with Docker and Kubernetes.
• Ability to create unit and integration tests using tools such as xUnit, NUnit, Moq, FluentAssertions, or Testcontainers.
• Knowledge of application security, including OAuth2, OpenID Connect, JWT, and identity management systems.
• Teamwork and effective communication skills.
• Nice to have:
  • Experience with IoT platforms and protocols (MQTT, AMQP, Modbus, SNMP, IEC 61850).
  • Knowledge of Keycloak.
  • Experience with ScyllaDB or Cassandra.
  • Knowledge of Terraform and Helm.
  • Knowledge of PKI and mTLS authentication.
  • Experience with multi-tenant architecture.
  • Knowledge of monitoring and observability tools (Prometheus, Grafana, Loki).
  • Experience with Azure DevOps.
  • Knowledge of Event Sourcing, CQRS, and gRPC communication patterns.
  • Experience in projects related to industrial automation, energy, SCADA, or power grids.
  • Good knowledge of English, both spoken and written.

Why Join Us

• Create solutions supporting the energy transformation and digitalization of critical infrastructure.
• Work on an IoT platform supporting thousands of devices and massive data volumes.
• Develop skills in the modern.NET ecosystem, Kubernetes, and Industrial IoT.
• Solve complex problems related to distributed systems and high scalability.
• Collaborate with an experienced, international team of specialists.
• Have a real impact on the architecture and direction of product development.
• Benefit from modern engineering practices and a supportive environment for professional growth.

Benefits

• Stable projects and opportunities for change.
• Technology Guilds.
• Solid tools.
• Speaker slots at conferences.
• Events and integrations.
• Charitable activities.

Recruitment Process

1. Submit your CV.
2. Recruitment interview.
3. Technical verification.
4. Interview with a partner.
5. Receive a job offer.
6. Welcome to our team!

Have Questions?

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Check the FAQ.

LinkedIn

Adrianna Grzechowiak

Junior IT Recruitment Specialist

+48 790 209 797

[email protected]

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