Lead Juniper & AWS Cloud Network Engineer

About Zappsec

Zappsec is an infrastructure and cybersecurity engineering company focused on helping organizations modernize complex environments across cloud, networking, and security.

Our teams work on large-scale transformation programs involving AWS, Azure, enterprise networking, zero trust, cloud security, automation, and data centre migrations. We are looking for engineers who can combine strong hands-on technical skills with the ability to own design decisions and lead critical migration workstreams.

Zappsec is seeking an experienced Lead Juniper & AWS Cloud Network Engineer to lead network engineering activities for a large-scale data centre to AWS migration.

The environment includes an established Juniper and Cisco network estate, complex routing, hybrid connectivity, security controls, and mission-critical applications being migrated to AWS.

This is a senior hands-on engineering role. You will be expected to understand the existing network, translate on-premises designs into AWS-native architectures, troubleshoot complex routing and connectivity issues, and lead migration activities through design, testing, cutover, and stabilization.

You will work closely with cloud architects, application teams, SREs, security engineers, infrastructure teams, and customer network teams.

Key Responsibilities Lead the network workstream for migration of enterprise applications and infrastructure from on-premises data centres to AWS

Assess existing Juniper and Cisco network configurations, routing domains, VLANs, VRFs, firewall policies, VPNs, and connectivity dependencies

Translate existing network designs into AWS architectures using services such as: Amazon VPC

AWS Transit Gateway

AWS Direct Connect

Site-to-Site VPN

VPC route tables

Network ACLs and security groups

AWS Network Firewall and third-party firewall platforms where applicable

Design and implement hybrid connectivity between data centres and AWS

Design and troubleshoot BGP routing across Direct Connect, VPN, Transit Gateway, and on-premises routing infrastructure

Analyze route advertisements, route filtering, prefix lists, route policies, asymmetric routing, and convergence behavior

Support migration of application network dependencies including DNS, load balancing, firewall policies, NAT, ingress, egress, and inter-VPC connectivity

Develop migration network designs that minimize downtime and support controlled application cutovers

Define network migration sequencing, validation procedures, rollback plans, and cutover runbooks

Lead troubleshooting during migration events and production cutovers

Validate network resiliency, redundancy, routing convergence, throughput, latency, and failover behavior

Identify and resolve complex network issues across Layer 2, Layer 3, routing, firewall, VPN, DNS, and cloud networking layers

Apply network security best practices including segmentation, encryption, firewall controls, DDoS protection, and least-privilege connectivity

Automate repeatable networking tasks using Terraform, Ansible, Python, APIs, or similar tooling

Review network configurations and infrastructure-as-code changes through peer review and change-control processes

Create clear architecture diagrams, low-level designs, implementation plans, operational runbooks, and troubleshooting procedures

Provide technical leadership and mentoring to network and cloud engineers

Act as a senior technical interface between customer network teams, cloud teams, application owners, security teams, and project leadership

Required Experience 10+ years of enterprise networking experience with strong hands-on experience in Juniper and/or Cisco environments

2–3+ years operating in a Lead, Principal, Senior Architect, or equivalent technical leadership role

Strong hands-on experience with Juniper routing and switching platforms

Strong understanding of Cisco networking technologies

Deep understanding of TCP/IP and enterprise routing

Strong hands-on experience with: BGP

OSPF

Route redistribution

Route filtering and policy

VRFs

VLANs

IP addressing and subnetting

NAT

Strong troubleshooting skills using routing tables, packet captures, flow analysis, logs, and device-level diagnostics

Strong understanding of DNS, DHCP, IPsec VPN, SSL VPN, and enterprise network security

Experience configuring and troubleshooting Juniper and/or Cisco switches, routers, and firewalls

Hands-on AWS networking experience, including: VPC architecture

Transit Gateway

Direct Connect

Direct Connect Gateway

Site-to-Site VPN

VPC route tables

Security groups and NACLs

Hybrid DNS and Route 53 Resolver

Multi-account and multi-VPC connectivity

Experience supporting enterprise data centre to AWS migration programs

Experience designing highly available hybrid connectivity and testing network failover scenarios

Experience with infrastructure and network automation using one or more of: Terraform

Ansible

Python

Jenkins

REST APIs

Git-based CI/CD workflows

Ability to read, understand, and rationalize large existing network configurations

Ability to lead technical discussions, communicate design trade-offs, and drive engineering decisions across multiple teams

Strong technical documentation and diagramming skills