Lead Infrastructure Engineer

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 / Ni...