About Telnyx

Telnyx is an industry leader that's not just imagining the future of global connectivity—we're building it. From architecting and amplifying the reach of a private, global, multi-cloud IP network, to bringing hyperlocal edge technology right to your fingertips through intuitive APIs, we're shaping a new era of seamless interconnection between people, devices, and applications.

We're driven by a desire to transform and modernize what's antiquated, automate the manual, and solve real-world problems through innovative connectivity solutions. As a testament to our success, we're proud to stand as a financially stable and profitable company. Our robust profitability allows us not only to invest in pioneering technologies but also to foster an environment of continuous learning and growth for our team.

Our collective vision is a world where borderless connectivity fuels limitless innovation. By joining us, you can be part of laying the foundations for this interconnected future. We're currently seeking passionate individuals who are excited about the opportunity to contribute to an industry-shaping company while growing their own skills and careers.

The Role

We’re looking for a Mobile Core Network Engineer to join the team responsible for Telnyx’s global mobile core network. You’ll own the infrastructure that powers our wireless platform — keeping it reliable, scalable, and ready for what comes next. This is a hands-on role spanning network operations, deployment automation, and incident response.

What You’ll Do

Network Operations & Infrastructure

Deliver and maintain core network services across global datacenters — ensuring high availability of PGWs, DRAs, GTP proxies, HSS, and STPs
Design redundancy patterns (failover, active-active, disaster recovery) and drive service localisation in new regions
Manage the GTP proxy fleet and DRA infrastructure: routing rules, IMSI translation, realm routing, and peer management
Monitor traffic growth, forecast demand, and scale infrastructure ahead of need

Automation & Deployment

Build and maintain Ansible playbooks and CI/CD pipelines for consistent, repeatable infrastructure changes
Operate and evolve the signalling plane — Diameter, GTP-C/U, SS7 MAP — across roaming partner interconnects
Design and maintain network connectivity: GRX/IPX peering, inter-datacenter tunnels, SCTP multihoming, and firewall rules

Observability & On-Call

Build dashboards and alerting to catch issues before they become incidents
Participate in on-call rotation for wireless infrastructure incidents

What We’re Looking For

Solid understanding of 3GPP EPC architecture: PGW, SGW, HSS, DRA, PCRF, STP, and their interfaces (S6a, S8, S5, Gx, S1-MME)
Experience operating and troubleshooting mobile core network elements in production
Strong networking fundamentals: IP routing, BGP/OSPF, VLANs, GRE/IPsec, SCTP, and packet-level troubleshooting (tcpdump/tshark)
Strong Linux skills: systemd, network configuration, performance tuning, and scripting
Hands-on experience with infrastructure automation — Ansible, Terraform, or equivalent
Familiarity with containerised environments (Docker, Kubernetes) and CI/CD pipelines
Experience with monitoring stacks: Prometheus, Grafana, Alertmanager
Experience with AWS or similar cloud infrastructure

Nice to Have

Experience with Diameter Routing Agents (freeDiameter or commercial DRAs) or GTP proxy platforms
Knowledge of multi-IMSI SIM architectures, VoLTE/IMS, or roaming models (S8HR, LBO)
Familiarity with IPX/GRX peering, GSMA roaming standards (IR.34), or network automation tooling (Netbox, NAPALM)
Experience with Elixir, Go, or Python in a network infrastructure context

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Mobile Core Network Engineer

Job Description