Notes

Notes & Cheat Sheets #

A personal collection of quick references, cheat sheets, configs, and reminders across my homelab, Kubernetes, and daily workflow.

⚡ Quick Commands & One-Liners #

Kubernetes & Argo CD #

# Force Argo CD hard refresh on an application
argocd app get <app-name> --hard-refresh

# Quick pod debug shell
kubectl run debug --rm -i --tty --image=nicolaka/netshoot -- /bin/bash

# Watch pod resource usage
kubectl top pods -A --sort-by=memory

Nix & NixOS #

# Enter project dev shell
nix-shell

# Update flake inputs
nix flake update

# Clean up old generations
nix-collect-garbage -d

OpenTofu / Terraform #

# Target specific module
tofu apply -target=module.network

# Format and validate
tofu fmt -recursive && tofu validate

🛠️ Infrastructure as Code & Dev Environments #

Brief overview of how things are provisioned:

  • OpenTofu: Manages cloud VMs on UpCloud, UniFi switches/VLANs, and Proxmox LXCs.
  • Cloudflare: DNS records, Zero Trust tunnels, and Access SSO applications managed declaratively.
  • GitOps: Argo CD tracks the conordot/kubernetes repository and auto-reconciles deployments.
  • Dev Shells & Containers: Nix shells and devcontainers for isolated, zero-drift developer environments.

Quick shell.nix Starter #

{ pkgs ? import <nixpkgs> {} }:
pkgs.mkShell {
  buildInputs = with pkgs; [ opentofu kubectl kubernetes-helm k9s jq ];
}

See Dev Shells & Environments for complete examples across Nix and Devcontainers.

🖧 Homelab Quick Reference #

  • Subnets / VLANs:
    • VLAN 1: Default management (192.168.1.0/24)
    • VLAN 3: Applications
    • VLAN 4: Homelab & IoT (192.168.86.0/24)
  • Proxmox LXC Nesting:
    • If running K3s or Docker inside unprivileged LXC, ensure nesting=1 and keyctl=1 are enabled in container features.

💻 Workstation & Hardware #

  • Primary: MacBook Pro (Apple Silicon)
  • Hypervisor: Lenovo Mini-PC (Proxmox VE 9.x)
  • Network: UniFi Cloud Gateway Max + x3 USW Ultra PoE switches
  • SBCs: Raspberry Pi 4 (Lightweight edge services)

📌 Scratchpad & References #

  • Projects & Things I’ve Built — An anonymised summary of platform engineering, cloud migrations, and security architectures I’ve delivered.
  • Experiment with Actions Runner Controller (ARC) for ephemeral GitHub runners.
  • Migrate local secrets to SOPS / Age encryption.
  • Set up an isolated playground VLAN for CTF / security challenges.
  • Explore Trusted Execution Environments (TEEs) and remote attestation.
  • Compare zk-STARK constructions and their practical tooling.
  • Build a small Secure Multi-Party Computation (SMPC) example.