Senior Developer Ultimate Guide 2026

1. Linux fundamentals — The Basics Processes vs threads fork(), exec(), signals File descriptors Pipes and sockets /proc and /sys Permissions, users/groups, capabilities systemd Linux namespaces cgroups seccomp mount namespaces / overlay filesystems TCP/IP basics Routing, DNS, bridges, NAT Basic Linux storage concepts Debugging with: ps top / htop strace lsof ss ip mount journalctl dmesg --- 2. Containers — "Docker packages an application." MODEL Learn: Docker architecture OCI Docker images Image layers Registries containerd runc Linux namespaces cgroups container networking container security rootless containers bind mounts volumes overlay filesystem Basic Container Ideas for Practice. Use a low level language like Rust, C++, Go, Zig or C to: 1. Create a child process 2. Put it in a new PID namespace 3. Create a mount namespace 4. Change its root filesystem 5. Configure networking 6. Apply a cgroup limit 7. Execute /bin/sh You will learn more from that than from watching ten Docker tutorials. --- 3. Virtualization Understand the difference: Learn: QEMU KVM virtual CPUs virtual memory device virtualization virtio VM networking VM storage hypervisor vs emulator hardware virtualization KVM architecture Then learn why projects such as RustVMM and Firecracker exist. You don't necessarily need to implement a hypervisor immediately. You should be able to explain what happens when: "I start a VM." --- 4. Systems programming For this specific job, I'd prioritize: C/C++ → Go → Rust Pick one systems language and become genuinely good at it. For Go, learn: pointers interfaces goroutines channels mutexes race conditions networking Unix syscalls error handling profiling testing concurrency For C/C++, learn: pointers memory management stack vs heap processes threads synchronization syscalls sockets memory layout debugging with gdb For Rust: ownership borrowing lifetimes Result / Option traits concurrency unsafe Rust FFI --- 5. Networking You don't need CCNA-level knowledge, but you should understand: Know: TCP handshake ports sockets IP addresses CIDR routing tables ARP DNS NAT bridges virtual Ethernet pairs network namespaces firewalls Then build this: Actually configuring that with ip commands is excellent preparation. --- 6. Storage Learn the fundamentals: filesystems block devices partitions mounts inode page cache filesystem vs block storage RAID basics snapshots copy-on-write distributed storage concepts Then understand why Ceph matters in cloud infrastructure. You don't need to become a Ceph administrator for a junior role, but know roughly what: means. --- 7. Kubernetes Learn Kubernetes after Docker/Linux fundamentals. Understand: Learn: Pods Deployments Services ConfigMaps Secrets Volumes namespaces scheduling kubelet container runtime CNI CSI control plane etcd Then deploy a small application locally with MicroK8s, kind, or another local Kubernetes environment. --- 8. Canonical-specific projects Once the fundamentals are solid, start exploring: LXD MicroK8s Charmed Kubernetes OpenStack OVN OVS Ceph QEMU KVM RustVMM Firecracker Rockcraft Don't try to learn all of them. Instead, pick one container project + one virtualization project. For example: Then read actual source code and submit a small upstream contribution if possible. --- Weeks 1–2 — Linux Build a Linux lab. Learn: Build small programs that use processes, threads, pipes and sockets. Weeks 3–4 — Networking Build: Be able to troubleshoot it when it breaks. Weeks 5–6 — Containers Learn Docker/OCI/containerd/runc. Then implement a tiny container runtime. Weeks 7–8 — Go/Rust/C Pick one language and write increasingly low-level programs. I'd make your projects increasingly systems-oriented rather than typical CRUD applications. Weeks 9–10 — Virtualization Learn: Run and inspect your own VMs. Weeks 11–12 — Kubernetes + Canonical Deploy Kubernetes locally. Then investigate LXD, MicroK8s and one of RustVMM/Firecracker. --- Projects I'd put on your GitHub For a junior applicant, these would be much more compelling than another REST API: Project 1 — Mini container runtime Project 2 — Linux network namespace lab Create isolated namespaces and connect them through a bridge. Project 3 — Tiny VM manager A Go/Rust program that starts and manages QEMU/KVM VMs. Project 4 — Container monitoring tool showing: using /proc, cgroups and Linux APIs. Project 5 — Kubernetes operator/tool Absolutely. For this Canonical role, think of the interview/application as testing whether you can understand Linux internals, containers/VMs, networking/storage, and write systems software, rather than whether you already know every Canonical project. As a junior developer, I'd prepare in layers: 1. Linux fundamentals — highest priority You should be comfortable explaining and using: Processes vs threads fork(), exec(), signals File descriptors Pipes and sockets /proc and /sys Permissions, users/groups, capabilities systemd Linux namespaces cgroups seccomp mount namespaces / overlay filesyste…