Senior Middleware Administrator

📌 We are looking for a Senior Middleware Administrator on behalf of our client - a German company, one of the world leaders in the production of fragrances, perfumes, cosmetic ingredients and functional food additives.

Location: Remote (for now) / potential onsite visits

Wroclaw, Warsaw, or Krakow as occasional office visits may be required.

Employment Type: Full-time

Experience Required: Minimum 6+ years

Role Summary

The Senior Middleware Administrator is responsible for installation, configuration, administration, clustering, troubleshooting, performance tuning, security, and decommissioning of enterprise middleware platforms including JBOSS, WebLogic, Apache Tomcat, IBM WebSphere, GlassFish, and Payara. The role ensures stable, scalable, and secure middleware environments.

Key Responsibilities:

1. Installation & Configuration

• Install, configure, and upgrade JBOSS EAP, WebLogic, Tomcat, WebSphere, GlassFish, and Payara.

• Configure JVM parameters, domains, clusters, threads, data sources, JDBC, JMS, and deployment descriptors.

• Implement SSL/TLS certificates, keystores, truststores, and security configurations.

2. Administration & Maintenance

• Manage deployments, start/stop, domain controllers, managed servers, and service components.

• Maintain log rotation, backups, patching, and middleware resource cleanup.

• Perform performance profiling, heap dump/thread dump analysis.

3. High Availability & Clustering

• Configure load balancing and clustering for JBOSS, WebLogic, Tomcat, WebSphere, and Payara.

• Support distributed caching, session replication, and failover mechanisms.

• Conduct HA testing, DR failover, and cluster validation.

4. Performance Optimization

• Tune JVM (heap, GC algorithms), thread pools, connectors, and caching mechanisms.

• Troubleshoot high CPU, memory leaks, GC pauses, and application performance issues.

5. Security & Compliance

• Configure authentication, authorization, SSL/TLS, encryption, and policy enforcement.

• Harden middleware servers and enforce compliance standards.

6. Troubleshooting & RCA

• Analyze logs (server logs, GC logs, thread dumps, access logs).

• Troubleshoot HTTP errors, deployment failures, connectivity issues, and timeouts.

• Provide RCA for incidents and implement preventive measures.

7. Automation & Scripting

• Automate tasks with Bash, PowerShell, WLST, Jython, or shell scripts.

• Manage configuration version control (Git, SVN).

Decommissioning & Lifecycle Management

• Plan and execute middleware server decommissioning.

• Archive logs, clean unused configurations, update CMDB.

Required Skills

• 6+ years hands-on experience in JBOSS, WebLogic, Tomcat, WebSphere, GlassFish, Payara.

• Strong understanding of Java application hosting, JVM tuning, clustering, HA.

• Strong Linux/Unix and Windows OS knowledge.

• Good troubleshooting of logs, heap/thread dumps, and performance issues.

Preferred Skills

• Experience with Nginx, Apache HTTPD, or reverse proxies.

• Experience with containers (Docker/Kubernetes) for middleware workloads.

• Monitoring with Grafana, Prometheus, Dynatrace, AppDynamics.

• CI/CD integration for middleware deployments.

Certifications

• Middleware/Web Server certifications preferred.

• ITIL Foundation.

Behavioral Competencies

• Strong ownership and problem-solving skills.

• Excellent communication and documentation discipline.

• Ability to work independently and handle critical issues.

Shift Requirements

• Business hours with on-call support.

• Availability for maintenance windows and emergency fixes.

✅ Benefits:

• Work with modern technologies and international teams

• Long-term and stable cooperation

• Professional growth opportunities

📩 If you’re interested and meet the qualifications, please send your CV to Alina Pchelnikova at alina.pchelnikova@dcvtechnologies.co.uk