> Markdown version of [/jobs/ext/4551378-software-engineer-backend-senior-onshore](https://www.wearedevelopers.com/jobs/ext/4551378-software-engineer-backend-senior-onshore). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md).

---

# Software Engineer BackEnd Senior Onshore

- **Company:** Halian
- **Location:** Brussel, Belgium
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Continuous Integration, Database Theory, Software Engineering, Mainframe Programming, Backend, Software Version Control
- **Published:** November 4, 2026
- **Apply:** https://www.careerjet.be/jobad/beb4497100db12be30070c2108fb463c4e

## About the Role

* Strong hands-on experience in mainframe application development and maintenance.
 * Solid understanding of mainframe programming, database concepts, development workbenches, source control, and continuous integration/deployment practices.
 * Ability to translate complex business needs into effective functional and technical solutions.
 * Strong communication and interpersonal skills, with the ability to explain ideas in a clear and structured manner.
 * Ability to work effectively and autonomously in a complex environment involving multiple stakeholders; strong team-player mindset.
 * Excellent Dutch and English communication skills; experience within financial markets or investment-related environments is considered an advantage.

## Description

* Translate business requirements into clear functional and technical designs.
 * Develop, maintain, and enhance applications within a mainframe environment.
 * Work independently to quickly understand existing applications, processes, and functional requirements.
 * Participate in an on-call support rotation to ensure continuity of critical services.
 * Collaborate closely with both IT and business stakeholders across different teams.
 * Contribute to modernization and continuous improvement initiatives while maintaining existing solutions.