Key Responsibilities • Mainframe modernization enablement • Partner with application and platform teams to migrate and modernize mainframe-adjacent workloads (e.g., rehost/refactor components, distributed integrations, data movement patterns). • Design target-state infrastructure and transition architectures for Azure, including landing zones and platform services alignment. • Azure infrastructure engineering • Build and operate Azure core services: VNETs/subnets, routing, NSGs, Azure Firewall, Private Link, DNS, identity integrations, and resource organization (subscriptions, management groups, tagging). • Implement Infrastructure as Code (IaC) using Terraform/Bicep and integrate with CI/CD pipelines. • Hybrid connectivity & network performance • Design, implement, and troubleshoot on-prem ↔ Azure connectivity using ExpressRoute, VPN, Virtual WAN, and hub/spoke (or vWAN) architectures. • Configure and validate routing (BGP), MTU/MSS settings, latency/throughput baselines, and failover behavior. • Tune connectivity performance for critical flows (batch, file transfer, API, messaging, data replication), including bandwidth planning and QoS considerations where applicable. • Performance tuning & reliability • Identify and remediate bottlenecks across network, compute, storage, and platform services (e.g., VM sizing, disk throughput/IOPS, load balancing behavior, TCP tuning, connection pooling implications). • Establish monitoring/observability (Azure Monitor, Log Analytics, Network Watcher, Application Insights where relevant), SLOs, alerting, and runbooks. • Lead root cause analysis for performance incidents and drive preventative improvements. • Security, governance, and operational excellence • Apply cloud security best practices (least privilege, segmentation, private endpoints, key management) and ensure alignment with governance controls. • Produce clear design documentation, operational procedures, and knowledge transfer. Required Qualifications • 10+ years in infrastructure engineering (cloud and/or datacenter), with direct experience supporting modernization or migration from mainframe environments to distributed/cloud platforms. • Strong, practical experience with Microsoft Azure, especially: • Networking (VNET, routing, NSG, Azure Firewall, Private Link, DNS) • Connectivity (ExpressRoute, VPN, vWAN, hub/spoke) • Compute/storage fundamentals (VMs, disk performance, availability patterns) • Demonstrated ability to set up, troubleshoot, and performance-tune hybrid connectivity (latency, throughput, packet loss, MTU/MSS, routing, failover). • Infrastructure as Code experience (Terraform and/or Bicep/ARM) and Git-based workflows. • Strong troubleshooting skills and ability to work across teams (network, security, app, data). Preferred / Nice to Have • Experience with modernization patterns: rehost, replatform, refactor; familiarity with integration with mainframe systems (e.g., batch scheduling, file transfer, messaging, data replication). • Azure Landing Zone / CAF experience, policy/guardrails, and enterprise subscription design. • Experience with performance tools and methods (load testing coordination, network path analysis, packet capture interpretation, baseline/SLO definition). • Containers (AKS), API management, and/or messaging services (Service Bus, Event Hubs) exposure.