About Sirma  
Established in 1992, Sirma is one of the leading IT companies in Bulgaria. Since 2015, the company has been listed on the Bulgarian Stock Exchange. 
Sirma specializes in software development across multiple industries, including finance, insurance, healthcare, transportation, logistics, hospitality, retail, and e-government. With a team of more than 700 professionals, the company delivers cutting-edge software solutions tailored to address the specific business needs and challenges of our clients. Our projects range from short engagements to multi-year collaborations on turnkey products. 
As we believe that our employees are our greatest asset, we provide them with a collaborative environment and full support for their career and personal growth. 

About the role 
We are seeking a highly skilled Senior .NET Cloud/OS Engineer  to join our dynamic team for a long-term project in the logistics industry. The ideal candidate will possess a good understanding of programming principles, database management, data structures and algorithms. This role requires a comprehensive skill set and the ability to work on complex problems in backend development. 

Your responsibilities 
• Improve software autonomously and collaborate with the team 
• Develop and maintain scalable .NET and C# solutions 
• Build cloud applications using IoT, Microservices, and Serverless 
• Ensure reliability with Agile, TDD, and best practices 
• Optimize and maintain SQL/NoSQL databases 
• Work with Azure cloud platform 

Role's requirements 
• 6+ years of professional experience in C# and .NET 
• Experience with Cloud Providers - SaaS Development or IoT Cloud platforms 
• Deep knowledge of Microservices , Serverless and/ IoT paradigms 
• Experience with ASP.NET, REST, RPC, GraphQL 
• Extensive SQL and/or NoSQL experience (MongoDB preferred)  
• Cloud development skills (Azure preferred; AWS/GCP considered) 
• Familiarity with observability tools (AppInsights, DataDog, OpenTelemetry) 
• Proactive, self-driven, and improvement-focused 
• Bachelor’s degree in Computer Science or a related field 
• Excellent verbal and written English

Advantages 
• Hardware integration experience (MDB, RS232, Modbus, etc.) and troubleshooting firmware communication 
• Experience with IoT Cloud platforms such as IoTHub and IoT Core 
• Load testing expertise using Grafana k6, Apache JMeter, or Locust 
• Hands-on experience with big data, ETL, and platforms like Databricks, Azure Data Factory, Spark, or Snowflake 
• Azure certifications are highly welcome 

Why Sirma Should be your choice 
• Personal career path 
• Working with cutting-edge technologies 
• Cooperation with top professionals around the globe 
• Interesting case studies 
• Knowledge sharing 
• Innovative and dynamic projects 
• Individual or team professional training 
• Regular performance assessment 
• Additional paid vacation days for students 

Healthcare and compensation package 
• Additional health and dental insurance 
• Food discounts 
• Multisport card 
• Fruits at the office 
• Private parking zone 
• Referral bonus scheme 

Work-life balance 
• Sport events 
• Game and relax zone 
• Large terrace with great view 
• Flexible working time 
• Opportunity to work from every Sirma’s office 
• Charity campaigns 
• Regular team buildings and office parties 

Apply now! 
We're looking forward to meeting our next colleague. 😊 

We will contact only the candidates selected for further consideration. Confidentiality is guaranteed. We thank all candidates for applying.