Resources
Fast, practical reference — command cheat sheets, tool comparisons, and interview questions with answers.
Cheat sheets
Kuberneteskubectl cheat sheetThe complete kubectl reference, beginner to advanced: contexts, inspecting and creating resources, rollouts, debugging, RBAC, scheduling, and power-user JSONPath — with example output.DockerDocker CLI cheat sheetComplete Docker reference from first run to production: images, containers, volumes and networks, Compose, Dockerfile directives, BuildKit multi-stage builds, and runtime hardening flags.LinuxLinux command cheat sheetA complete Linux command reference for DevOps and security work: files and text, permissions, processes, users, disk, networking, systemd, packages, plus advanced awk/sed, tracing, and shell scripting — with example output.TerraformTerraform cheat sheetThe complete Terraform reference, beginner to advanced: the core workflow, formatting and validation, state surgery, workspaces, variables, modules, targeting, import/moved, and debugging — with example output.AnsibleAnsible cheat sheetThe complete Ansible reference, beginner to advanced: inventory and connectivity, ad-hoc modules, running and controlling playbooks, variables and facts, Vault, roles and Galaxy, templating, and debugging — with example output.HelmHelm cheat sheetThe complete Helm reference, beginner to advanced: repos, install and upgrade, inspecting releases, values and templating, chart authoring, dependencies, rollback, testing, and OCI registries — with example output.GitGit cheat sheetThe complete Git reference, beginner to advanced: config, staging and committing, branching, history, remotes, merge and rebase, undoing changes, stash, tags, and power tools like bisect, reflog, cherry-pick and worktrees — with example output.BashBash scripting cheat sheetThe complete Bash reference, beginner to advanced: script safety, variables and expansion, conditionals, loops, functions, arrays, string manipulation, parameter expansion, process substitution, and traps/debugging — with example output.VaultHashiCorp Vault cheat sheetA complete Vault reference, beginner to advanced: connect and authenticate, KV v2 secrets, auth methods, policies, dynamic database/PKI/transit secrets, and operator tasks — with example output.OPAOPA & Rego cheat sheetOpen Policy Agent and the Rego language, beginner to advanced: the opa CLI, Rego rules and idioms, testing, conftest for config files, bundles and the decision API, and Gatekeeper — with example output.KustomizeKustomize cheat sheetTemplate-free Kubernetes customization, beginner to advanced: build and apply, the kustomization.yaml fields, generators, image/replica setters, patches, and the bases/overlays/components model — with example output.Argo CDArgo CD cheat sheetThe Argo CD GitOps engine, beginner to advanced: login, application create/sync/rollback, live diff, repos and clusters, projects and RBAC, plus app-of-apps, ApplicationSets, and sync waves/hooks — with example output.GitLab CIGitLab CI/CD cheat sheetThe .gitlab-ci.yml reference, beginner to advanced: stages and jobs, rules and workflow, artifacts/cache/needs, variables and OIDC secrets, environments, includes/extends/anchors, security scanning, and the glab CLI — with examples.PythonPython for DevSecOps cheat sheetPractical Python for operators and security engineers, beginner to advanced: running scripts, virtualenvs and dependency locking, handy stdlib one-liners, dependency/SAST scanners, crypto and hashing, and lint/type/test tooling — with examples.
Comparisons
CompareTerraform vs OpenTofuHow the OpenTofu fork differs from Terraform on licensing, features, and drop-in compatibility — and which to choose in 2025.CompareHelm vs KustomizeTemplating vs overlays for Kubernetes manifests — when to reach for Helm charts and when Kustomize overlays are the better fit.CompareArgo CD vs FluxThe two CNCF-graduated GitOps engines compared — UI, architecture, multi-tenancy, and how each reconciles Git to the cluster.CompareDocker vs PodmanDaemon vs daemonless containers — rootless security, compatibility, and whether Podman can really be a drop-in for Docker.CompareAnsible vs Chef vs PuppetThe three classic configuration-management tools compared — agent model, language, and where each still fits today.
Interview questions
KubernetesKubernetes interview questionsKubernetes interview questions from fresher to 6+ years — pods and services, workloads and scheduling, networking, storage, RBAC, and control-plane architecture, each answer tagged by experience level.DockerDocker interview questionsDocker and container interview questions from fresher to senior — images and layers, multi-stage builds, runtime and networking, and container security and isolation, tagged by experience level.LinuxLinux interview questionsLinux interview questions for DevOps and SRE roles, fresher to senior — permissions, processes and signals, performance troubleshooting, and networking and boot, tagged by experience level.TerraformTerraform interview questionsTerraform and IaC interview questions from fresher to senior — state and workflow, the language, lifecycle and operations, and scaling and security, each answer tagged by experience level.CI/CDCI/CD interview questionsCI/CD interview questions from fresher to senior — pipeline fundamentals, practical pipeline design, deployment strategies, and secure CI/CD, each answer tagged by experience level.GitOpsGitOps interview questionsGitOps interview questions from fresher to senior — core principles, Argo CD and Flux, environment promotion and repo structure, and advanced multi-cluster and progressive delivery, tagged by experience level.Policy as CodePolicy-as-code interview questionsPolicy-as-code interview questions from fresher to senior — fundamentals, Rego and testing, Kubernetes enforcement with Gatekeeper and Kyverno, and advanced authz and supply-chain policy, tagged by experience level.VaultVault & secrets management interview questionsHashiCorp Vault and secrets-management interview questions from fresher to senior — fundamentals, dynamic secrets and engines, Kubernetes and app integration, and operations and security, tagged by experience level.ObservabilityObservability & SRE interview questionsObservability and SRE interview questions from fresher to senior — the three pillars, Prometheus and metrics, logging and tracing, and SLOs and incident response, each answer tagged by experience level.DevSecOpsDevSecOps & supply-chain security interview questionsDevSecOps and software-supply-chain interview questions from fresher to senior — shift-left fundamentals, scanning in the pipeline, supply-chain security, and runtime and culture, each answer tagged by experience level.