Wholesale Billing IT Specialist (f/m/d) @ A1 Competence Delivery Center

Strength. Care. Growth

A1 Competence Delivery Center is a vital component of A1’s telecommunications business. Acting as an expertise hub, CDC is dedicated in delivering full range of high-quality IT, network, financial and other services to support A1’s operations across all OpCos, independent of location. 

Using the power of A1 Group and leverage synergies, CDC enables transparency of resources, key skills and knowledge expansion and personal career growth opportunities’ enhancement, paired with job stability. 

You will know we are the right place for you, if you are driven by:

• Opportunities to learn and build your career.
• Meaningful work in a stable and fast-paced company.
• Diversity of people, projects, and platforms.
• A supportive, fun, and inspiring place to work.

Role Overview:

End-to-end owner of carrier and wholesale billing operations, driving workflow optimization, troubleshooting complex CDR/EDR-based issues, and coordinating cross-functional delivery to ensure accurate, stable, and compliant billing across markets.

Role insights:

• Operate and continuously improve carrier and wholesale billing workflows end‑to‑end (file ingestion, mediation, rating, reporting, invoicing) across multiple markets
• Provide 2nd/3rd level support by analyzing, troubleshooting and resolving processing and mapping issues based on CDR/EDR data, logs and database checks
• Act as key interface between business teams (wholesale / interconnection), external partners and software vendors – from clarifying new requirements (partners, traffic flows, mapping rules, MVNO / application‑SMS scenarios) to testing and rolling out changes
• Ensure performance, stability and compliance of batch‑ and file‑based billing processes (e.g. re‑rating, EDR extracts, month‑end runs) through effective monitoring, logging and auditability
• Maintain clear and up‑to‑date technical and functional documentation (designs, mappings, runbooks, operations manuals, test descriptions).

What Makes You Unique:

• Several years of hands-on telco billing/rating experience (wholesale, interconnect, roaming)
• Strong knowledge of CDR/EDR structures and telecom use cases (voice, SMS, application‑SMS, MVNO, porting, home routing)
• Expert in relational databases (Oracle, MSSQL) and SQL for analysis and performance‑critical investigations
• Practical programming experience (Java) for billing component analysis and enhancement
• Proven operation and troubleshooting of batch/file processing chains in production, including alert handling on Windows Servers
• Strong analytical mindset, high attention to detail and structured work style in critical environments
• Able to explain complex technical topics clearly to business stakeholders and work effectively across markets and teams (business and technical departments)
• Team player with end‑to‑end ownership and readiness to take responsibility in incidents
• Fluent in English; German is a plus
• Key skills: Java, Windows Server Management, Oracle/MSSQL, Jenkins pipelines, Cucumber test automation.

Our gratitude for the job done will be eternal, but we’ll also offer you:

•  Valuable experience in one of the fastest-growing and most innovative industries.
•  Challenging assignments with strong opportunities for personal and professional growth in a multinational environment.
•  Hybrid working model supporting a healthy work-life balance.
•  Thousands of online and in-person Learning opportunities for you to grow.
•  Modern, open, and friendly work environment that fosters continuous learning and the development of both technical and soft skills.
•  Special employee tariffs and a wide range of attractive employee benefits

If you have any questions,  please do not hesitate to contact Svetlina Vazharova.