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 visitsWroclaw, Warsaw, or Krakow as occasional office visits may be required.Employment Type: Full-timeExperience Required: Minimum 6+ yearsRole SummaryThe 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 & ConfigurationInstall, 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 & MaintenanceManage 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 & ClusteringConfigure 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 OptimizationTune JVM (heap, GC algorithms), thread pools, connectors, and caching mechanisms.Troubleshoot high CPU, memory leaks, GC pauses, and application performance issues.5. Security & ComplianceConfigure authentication, authorization, SSL/TLS, encryption, and policy enforcement.Harden middleware servers and enforce compliance standards.6. Troubleshooting & RCAAnalyze 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 & ScriptingAutomate tasks with Bash, PowerShell, WLST, Jython, or shell scripts.Manage configuration version control (Git, SVN).Decommissioning & Lifecycle ManagementPlan and execute middleware server decommissioning.Archive logs, clean unused configurations, update CMDB.Required Skills6+ 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 SkillsExperience 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.CertificationsMiddleware/Web Server certifications preferred.ITIL Foundation.Behavioral CompetenciesStrong ownership and problem-solving skills.Excellent communication and documentation discipline.Ability to work independently and handle critical issues.Shift RequirementsBusiness hours with on-call support.Availability for maintenance windows and emergency fixes.✅ Benefits:Work with modern technologies and international teamsLong-term and stable cooperationProfessional growth opportunities📩 If you’re interested and meet the qualifications, please send your CV to Alina Pchelnikova at [email protected]