Senior .NET Developer

WHO WE ARE?

ALTEN – A Global Leader in Engineering and IT Services

Founded in France in 1988, the ALTEN Group is a leading technological partner serving the world’s largest clients. In 2023, it achieved revenues exceeding 4.07 billion euros and employs over 57,000 people, 88% of whom are engineers and IT experts.

ALTEN Polska has been operating for 13 years, supporting its clients' innovation, research and development, and IT systems. It has offices in Kraków, Warsaw, Wrocław, Gdańsk, and Poznań.

It serves key industries such as aerospace, space, industrial solutions, automotive, railway, energy, finance, telecommunications, and retail.

Areas of expertise: business analysis, cybersecurity, artificial intelligence, data analysis and cloud solutions, application development, software testing, project management, embedded software, quality management, industrialization, digital transformation, and industrial engineering.

For more information, visit: http://www.altenpolska.pl

I am looking for experienced specialists for an Senior .NET Developer position for our client in the logistics industry.

Project Info:

📅Start: December 1, 2026

📍Location: hybrid work in Warsaw (3 days per week working from Warsaw office)

Main tasks:

• Maintain and extend the Windows Service (C#, .NET Framework), including its multi-threaded, timer-driven import and export processing.

• Develop and optimise SQL Server data access: stored procedures, Dapper-based repositories, and handling of deadlocks, locking and performance issues.

• Maintain mappings between canonical data models for shipments, status events, milestones and customs declarations, using AutoMapper and custom merge logic.

• Maintain and update WCF/SOAP integrations, such as the DAAC master data and configuration services and the export service agents.

• Provide 2nd/3rd-level production support: analyse data issues, reprocess or correct records, and resolve incidents together with operations and business teams.

• Document the current solution and contribute to its modernisation roadmap, e.g. migrating to modern .NET, standard dependency injection and REST-based integrations.

• Drive quality through unit and integration testing

Requirements:

• You are an experienced, quality-focused developer who is comfortable working with established enterprise systems, enjoys solving complex data problems, and communicates clearly with both technical and business stakeholders.

• 5+ years of proven experience as a .NET Developer, Software Engineer, or in a similar role.

• Strong proficiency in C# and .NET Framework 4.x, including Windows Services, multithreading with the Task Parallel Library.

• Solid experience with Microsoft SQL Server and T-SQL: backup, stored procedures, query tuning, transactions, isolation levels and deadlock analysis.

• Hands-on experience with WCF/SOAP services, including generating and maintaining service references and configuring bindings and endpoints.

• Experience with XML serialization and XSD schemas, XLST maps, and with object mapping libraries such as AutoMapper

• Familiarity with dependency injection (e.g. Unity)

We offer:

- a full-time contract (B2B/employment contract)

- well-defined career path at the European leader in engineering & IT consulting

- participation in company conferences, trainings, workshops, integration meetings, etc.

- certification and training opportunities

- opportunity to relocate and work in different ALTEN Polska branches

- after completion of the project, opportunity to engage in a subsequent one within the company.

- introduction and cooperation with dedicated Business Development Manager

- work in company with #GreatePlaceToWork Certificate

Benefits:

- Medicover medical care

- Medicover dental care

- Medicover Benefits platform / Medicover Sport card

- employee referral program

- layette for a newborn employee’s child

- group life insurance

- pension scheme

Join our team and let’s build tomorrow’s world today!

NOTICE: We kindly inform you that we will contact the selected candidates.