Networking: TCP/IP, BGP, OSPF, MPLS, QoS, IPsec, VPNs, L2/L3 switching and routing, 2G/3G/4G/5G packet core
Programming: C, Go, Python, JavaScript, and many others, but lets keep those for now 🙂 ...
Systems: Linux, Nix/NixOS, distributed systems, Raft consensus, key-value stores, reproducible infrastructure
Cloud & Infrastructure: Docker, Kubernetes, Helm, Ansible, multi-tenant cloud operations
Databases: PostgreSQL, MySQL, MongoDB
Tools & Operations: Git, CI/CD concepts, monitoring, production troubleshooting, technical documentation