Middleware L3 Support Engineer

Job Summary:

We are seeking a Middleware L3 Support Engineer / Administrator with 7–9 years of hands-on experience supporting enterprise integration and API platforms in production. The role will own technical troubleshooting, service restoration, problem management, performance optimization, security remediation, and controlled change execution across Landmark’s middleware ecosystem. The ideal candidate can analyse complex cross-platform failures, coordinate with application, infrastructure, network, cloud, security, and vendor teams, and drive incidents through to root-cause closure.

Middleware Scope:

IBM API Gateway; IBM App Connect Enterprise (ACE) and IBM MQ; Azure-hosted ACE and MQ; Kong API Gateway; NGINX API Gateway / reverse proxy; Oracle Integration Cloud (OIC); Oracle Retail Integration Bus (RIB); Managed File Transfer (MFTP); and Azure Service Bus (ASB).

Responsibilities:

Platform Operations:

• Install, configure, administer, monitor, and support the in-scope middleware platforms across non-production and production environments, including high-availability and disaster-recovery configurations.
• Perform L3 diagnosis and resolution for API, message-flow, queue, integration, file-transfer, authentication, connectivity, latency, throughput, and availability issues; restore service within agreed SLA targets and escalate with complete technical evidence when required.
• Manage IBM ACE/MQ and Azure ACE/MQ components, including message flows, queues, channels, listeners, policies, certificates, connectivity, retries, dead-letter handling, and message reprocessing.
• Support IBM API Gateway, Kong, and NGINX API Gateway / reverse-proxy services, including API publication, routing, policies, authentication, rate limiting, TLS, upstream connectivity, logging, and traffic troubleshooting.
• Support OIC, Oracle RIB, MFTP, and Azure Service Bus integrations, including orchestration, mappings, schedules, endpoints, subscriptions, transfers, failed-message handling, and replay/recovery procedures.

Integration and API Management:

• Create, configure, and troubleshoot API endpoints, routes, integrations, message flows, transformations, and secure system-to-system connectivity in line with approved standards.
• Integrate middleware services with Active Directory / LDAP and enterprise identity services, including authentication, authorization, service accounts, groups, certificates, and secrets.
• Validate payloads, schemas, headers, routing rules, queues/topics, correlation IDs, and end-to-end transaction traces across dependent applications.

Incident, Problem, and Change Management:

• Provide 24x7/on-call or shift-based production support as required; participate in incident triage, war rooms, major-incident communications, and stakeholder updates.
• Lead root-cause analysis for recurring or major incidents and produce actionable RCA reports with corrective and preventive actions; maintain known-error and runbook content.
• Plan and execute upgrades, patches, configuration changes, certificate renewals, deployments, failover tests, and rollback procedures through approved ITIL change controls.

Performance, Security, and Resilience:

• Monitor capacity, throughput, latency, queue depth, API error rates, JVM/runtime health, resource utilization, and integration backlogs; tune configurations to improve reliability and scalability.
• Apply security and operational controls, including TLS/mTLS, certificate and secret lifecycle, least privilege, vulnerability remediation, access reviews, audit logging, and secure configuration baselines.
• Maintain and test backup, recovery, high-availability, disaster-recovery, and business-continuity procedures for middleware services.

Observability and Documentation:

• Use enterprise monitoring, centralized logging, alerting, tracing, and ticketing tools to detect issues early and provide clear diagnostic evidence.
• Maintain accurate architecture diagrams, configuration records, dependency maps, support matrices, operational runbooks, SOPs, deployment records, and knowledge articles.

Qualifications:

• 7–9 years of relevant experience in middleware engineering, administration, integration, or production L3 support; experience in retail, e-commerce, or other high-volume environments is preferred.
• Strong hands-on experience with IBM ACE/App Connect Enterprise and IBM MQ, including message flows, queues, channels, listeners, troubleshooting, and performance tuning.
• Practical experience with at least two API gateway technologies, with preference for IBM API Gateway, Kong, and NGINX; experience with API lifecycle management, policies, routing, authentication, and TLS.
• Working knowledge of Azure-hosted ACE/MQ and Azure Service Bus, plus experience with OIC, Oracle RIB, and managed file-transfer platforms such as MFTP.
• Experience with REST/SOAP APIs, HTTP/S, JSON, XML, XSD/WSDL, OAuth 2.0, LDAP/Active Directory, certificates, SFTP/FTPS, TCP/IP, DNS, and load balancers.
• Proficiency in Linux/Unix administration and scripting/automation using Shell and/or Python; Ansible, CI/CD, Docker, Kubernetes, or infrastructure-as-code experience is desirable.
• Experience with monitoring and log-analysis tools, ITIL-based incident/problem/change processes, and structured RCA documentation.
• Strong analytical, communication, stakeholder-management, and vendor-coordination skills; able to work under pressure during high-severity production incidents.