C# .net Software Engineer (senior) – Application Support & Systems Integration FRENCH/ENG

Location: Brussels / Zaventem Start: ASAP. FREELANCE

We are looking for a hands-on Software Engineer to join a technical team responsible for maintaining, supporting and integrating business-critical software applications.

The role combines software development, application support, troubleshooting, systems integration and configuration. You will take ownership of production issues, perform root-cause analysis, implement fixes and work across application, database, infrastructure and networking layers.

Key Responsibilities

- Provide 2nd/3rd line application support and resolve complex production issues.
- Diagnose problems across software, databases, networks and system interfaces.
- Perform root-cause analysis and implement permanent fixes.
- Develop and maintain system integrations and data interfaces.
- Work with APIs, messaging systems and real-time data flows.
- Configure and maintain high-availability and redundant environments.
- Support software deployments, testing and system configuration.
- Collaborate with developers, infrastructure teams, technical teams and external stakeholders.
- Produce technical documentation, troubleshooting guides and operational procedures.
- Contribute to software stabilisation, refactoring, automation and CI/CD initiatives.
- Help modernise test environments and improve overall system reliability.

Technical Skills

Programming

- C# / .NET Framework / .NET Core
- Python (an advantage)
- PowerShell / Bash
- Multi-threaded and event-driven applications

Databases

- SQL Server / PostgreSQL
- Complex SQL queries and stored procedures
- Performance tuning
- Database redundancy/failover




- Data migration and ETL

Integration & Messaging

- OPC UA / industrial communication
- MQTT / AMQP
- TCP/IP and socket-level troubleshooting
- XML / JSON
- Message brokers
- Real-time data processing and event-driven architectures

Infrastructure

- Windows Server
- Linux / Red Hat / CentOS
- VMware / Hyper-V
- VPN, RDP, SSH
- Remote access and secure connectivity

DevOps & Tools

- Git / GitLab / GitHub
- CI/CD pipelines
- Docker
- Jira / Confluence
- ITIL / service management

Networking & Security

- TCP/IP
- Firewalls, proxies and NAT
- TLS/SSL and certificate management
- Secure remote access
- Network segmentation and DMZs

Experience Required

- 3+ years' experience in Software Engineering, Systems Integration, Application Support or a similar technical role.
- Strong debugging and root-cause analysis capability.
- Comfortable troubleshooting complex systems across multiple technical layers.
- Experience working in production/mission-critical environments is advantageous.
- Strong communication and technical documentation skills.
- Able to work independently while collaborating with technical and business stakeholders.

Nice to Have

- Industrial automation / SCADA / PLC experience
- Experience with DevOps and CI/CD
- Infrastructure-as-code exposure
- ITIL/service management experience
- French language skills
- Experience in logistics, transportation or other 24/7 operational environments

The mindset is crucial.

The ability to influence, change, want to change/improve and get stuck in!!

top firm, top management, lots of work. Not always easy and always a challenge!!

If you get to this bit, you must be keen and thorough (good work), email me direct, [email protected]

📌 C# .net software engineer (senior) – application support & systems integration french/eng (España)
🏢 Michael Bailey Associates
📍 España