Backend C# Engineer & Team Leader

Summary

Join ALTER SOLUTIONS as a Backend C# Engineer & Tech Leader to contribute to security and border control projects for a European institution. You will be responsible for designing, developing, and maintaining microservices-based applications. This role requires strong C# programming skills, experience with microservices architecture, and a minimum of 5 years of professional experience. The position offers a remote/hybrid work model from Warsaw, a B2B contract, and various benefits including professional development support, bonuses, healthcare, and more. The project is initially for one year with a high possibility of extension.

Requirements

• Have a strong background in developing web-based applications using a microservices architecture and expertise in migrating monolithic applications to microservices
• Hold a Bachelor’s degree in Software Engineering or a related field
• Possess strong programming skills in C#
• Have at least 5 years of proven professional experience, including designing and developing microservices-based applications for large-scale organizations
• Have an in-depth understanding of microservices architecture, including orchestration and choreography patterns (SAGA) within a Domain-Driven Design (DDD) approach
• Be able to develop, implement, and maintain scalable, loosely coupled microservices
• Have experience in building and deploying high-quality APIs (REST/WebSockets) for service communication and external integrations
• Be proficient in containerization technologies (Docker) and orchestration platforms (Kubernetes)
• Have experience working in Agile environments (Scrum), with the ability to collaborate effectively within a team, share knowledge, and mentor colleagues
• Be proficient in the English language (B2+/C1 level) and have strong communication skills

Responsibilities

• Gather and document requirements for microservices, design architectural solutions, prepare documentation, and identify potential risks and challenges
• Analyze the existing monolithic system, define microservice boundaries, refactor code for modularization, decouple components, and document the adopted approach
• Define API endpoints, implement required functionalities, align response formats, coordinate integration points, and conduct integration testing
• Assess current performance to identify bottlenecks, refactor code for efficiency, scale microservices, implement optimization strategies, and conduct performance testing
• Create and maintain comprehensive documentation on architecture, setup, and micro frontend usage, perform code reviews, and provide feedback to ensure continuous quality improvement
• Work closely with business analysts and architects to clarify and refine business needs
• Manage and coordinate teams involved in the design, development, and maintenance of microservices-based applications

Preferred Qualifications

• Possess an EU-CONFIDENTIAL (or higher) security clearance
• Have experience in a Senior or Lead Developer role, mentoring junior team members
• Have hands-on experience with Red Hat OpenShift (RHOS)
• Have a strong understanding of design patterns such as Service Discovery, Circuit Breaker, and API Gateway (preferably KONG)
• Be proficient in implementing event-driven architectures (EDA) using Kafka, along with experience working with asynchronous messaging systems
• Be familiar with distributed databases and data management strategies (SQL/NoSQL)
• Have knowledge of monitoring, logging, and distributed tracing tools (e.g., Prometheus, Grafana, ELK, Jaeger) in combination with a Service Mesh communication layer
• Have expertise in securing applications using token-based authentication mechanisms (JWT, OAuth2) and other security measures
• Have experience developing for cloud platforms (Azure, AWS) and their associated toolsets
• Have a background in building observability features for microservices
• Have a strong understanding of Domain-Driven Design (DDD)
• Have experience setting up and maintaining CI/CD pipelines for microservices deployment (Azure Agent, ArgoCD, Helm Charts) and working within a CI/CD environment using Azure DevOps
• Have knowledge of secure coding practices, including OWASP Top 10 security principles
• Be able to apply best practices, software development patterns, and methodologies (e.g., SOLID principles). Familiarity with UML notation
• Be proficient in Git workflows
• Have experience writing automated unit and integration tests

Benefits

• Access to local and international projects - Clients from France, Germany, Portugal, UK, and Benelux
• Professional development support - trainings, technical certificates, conference participation, foreign language classes, and soft skills trainings are subsidized for up to 2 000 PLN
• Bonus for recommending Candidates starting from 6 000 up to 10000 PLN
• Fully paid Medicover healthcare card
• Psychological support program WellBee
• Multisport card
• Regular integration events and gifts
• Long-term cooperation
• Relocation Program
• Remote/Hybrid work model from Warsaw
• B2B contract