Informix DBA engineer

Inetum is a European leader in digital services. Inetum’s team of 28,000 consultants and specialists strive every day to make a digital impact for businesses, public sector entities and society. Inetum’s solutions aim at contributing to its clients’ performance and innovation as well as the common good. Present in 19 countries with a dense network of sites, Inetum partners with major software publishers to meet the challenges of digital transformation with proximity and flexibility. Driven by its ambition for growth and scale, Inetum generated sales of 2.5 billion euros in 2023.

We are looking for an IBM Informix Database Engineer to join a production-focused service center supporting mission-critical database environments. This role is ideal for a highly skilled L3 specialist with deep expertise in Informix architecture, high availability, performance tuning and automation. You will ensure reliability and continuity across multi-customer infrastructures, leading major changes, advanced troubleshooting and 24/7 operations.

Responsibilities:

• Design and evolve Informix database architectures, including HA/DR, replication, storage layouts and hybrid deployment models;

• Perform advanced L3 administration, troubleshoot complex incidents and lead deep-dive analysis using Informix tooling;

• Monitor and optimize performance through SQL tuning, indexing strategies, statistics management and capacity tracking;

• Define and maintain backup, restore and disaster recovery strategies, including regular DR and failover testing;

• Lead major changes such as upgrades, migrations, storage redesigns and HA/DR improvements, ensuring safe deployments;

• Participate in 24/7 on-call rotation, handling critical incidents and coordinating with cross-functional technical teams;

• Develop automation scripts and contribute to CI/CD pipelines to industrialize provisioning, patching and monitoring;

• Implement and enforce security policies, including authentication, privileges, encryption, auditing and compliance;

• Produce and maintain technical documentation (architectures, runbooks, procedures) and enrich internal knowledge bases;

• Mentor junior DBAs and act as a subject-matter expert in technical committees and customer meetings.

• 5-10+ years of experience in production database administration, with strong hands-on expertise in IBM Informix;

• Solid background in Informix architecture, high availability, migrations, performance tuning and large-scale database operations;

• Experience working in multi-customer or service-center environments (MSP/outsourcing) is highly valued;

• Advanced knowledge of Informix engine components (dbspaces, chunks, logs, onstat/onmode/oncheck tooling, sysmaster/sysadmin);

• Strong expertise in Informix HA/DR technologies (HDR, RSS, SDS, Enterprise Replication, Connection Manager);

• Proven skills in performance tuning: query plan analysis, SQL optimization, indexing, fragmentation and statistics management;

• Solid understanding of backup/restore mechanisms (ON-Bar, ontape, logical logs, dbexport/dbimport) and complex recovery scenarios;

• Good knowledge of Linux/AIX environments, OS-level troubleshooting, virtualization (VMware) and storage architectures (SAN/NAS);

• Experience with scripting and automation (PowerShell, Python, Bash, Ansible) and contribution to CI/CD pipelines;

• Strong analytical mindset, ability to stay calm under pressure and perform effectively in on-call situations;

• Excellent communication skills and ability to collaborate with cross-functional technical teams;

• Organized, autonomous, customer-oriented and comfortable working in demanding, SLA-driven environments;

• Fluent English required; French or Dutch are considered a plus.