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0410 Caddy: HTTPS reverse proxy in five lines Caddy gets and renews TLS certificates on its own. Install it, write a Caddyfile with your domain and the port your app… Beginner · Step by step · Linux Article Deploying sites · Web servers & reverse proxies 15 Oct 2026
0420 cron and systemd timers: run something every night Schedule a script with crontab or a systemd timer: the five cron fields, environment and PATH pitfalls, logging, catching up missed runs… Beginner · Step by step · Linux Article cron & timers · Services & systemd 15 Oct 2026
0387 Install Python on Linux, macOS and Windows Install a current Python 3 with pip and venv on each desktop OS, check the version, and avoid the classic traps: python… Beginner · Step by step · Linux, macOS, Windows Article Environments & packages · Installing languages & tools 15 Oct 2026
0388 Install Go on Linux, macOS and Windows Install the Go toolchain from the official downloads or a package manager, set PATH so the go command and installed tools are… Beginner · Step by step · Linux, macOS, Windows Article Installing languages & tools 15 Oct 2026
0389 Install Java (OpenJDK) on Linux, macOS and Windows Install a current long-term-support OpenJDK with the compiler included, make java and javac available on the command line, and switch between versions… Beginner · Step by step · Linux, macOS, Windows Article Installing languages & tools 15 Oct 2026
0390 Install Git on Linux, macOS and Windows Install Git from your package manager, Xcode's command line tools or the Windows installer, confirm the version, and do the one-time configuration… Beginner · Step by step · Linux, macOS, Windows Article Installing languages & tools · Setup 15 Oct 2026
0391 Install Docker on Linux, macOS and Windows Docker Desktop or Docker Engine? Pick the right one for your OS, install it, and confirm with docker run hello-world. Covers the… Beginner · Step by step · Linux, macOS, Windows Article Docker basics · Installing languages & tools 15 Oct 2026
0392 Install Visual Studio Code on Linux, macOS and Windows Install VS Code from Microsoft's packages, Homebrew or winget, get the code command working in the terminal, and add the extensions you… Beginner · Step by step · Linux, macOS, Windows Article Command-line tools · Installing languages & tools 15 Oct 2026
0393 Install PostgreSQL on Linux, macOS and Windows Install the PostgreSQL server and the psql client on each desktop OS, start the service, connect as the postgres superuser and create… Beginner · Step by step · Linux, macOS, Windows Article Install & connect · Installing languages & tools 15 Oct 2026
0394 Install kubectl on Linux, macOS and Windows Install the Kubernetes command-line client with curl, a package manager or winget, verify it, and point it at a cluster with a… Beginner · Step by step · Linux, macOS, Windows Article Concepts · Installing languages & tools 15 Oct 2026
0395 Install Rust on Linux, macOS and Windows Install Rust the official way with rustup, which brings rustc, cargo and future updates, make sure a C linker is present, and… Beginner · Step by step · Linux, macOS, Windows Article Installing languages & tools 15 Oct 2026
0381 pre-commit hooks: catch mistakes before they are committed Install the pre-commit framework, configure hooks for whitespace, YAML and JSON syntax, large files, leaked private keys, Python linting and shellcheck, run… Beginner · Step by step · Linux, macOS, Windows Article Pipelines, runners & hooks · Setup 15 Oct 2026
0386 Install Node.js on Linux, macOS and Windows Get Node.js and npm on any desktop OS. Use a version manager (nvm or fnm) when you work on several projects, or… Beginner · Step by step · Linux, macOS, Windows Article Installing languages & tools · Node.js 15 Oct 2026
0344 ufw and firewalld: open and close ports Allow and remove ports and services on the two standard Linux host firewalls, restrict a port to one source network, and make… Beginner · Step by step · Linux Article Firewalls · Networking & firewalls 15 Oct 2026
0345 SSH keys: create, copy and use them Generate an ed25519 key pair, install the public key on a server with ssh-copy-id, keep the private key protected with a passphrase… Beginner · Step by step · Linux, macOS, Windows Article Keys & config · SSH 15 Oct 2026
0352 Harden a fresh Linux server in 30 minutes The baseline for any new Debian, Ubuntu or RHEL-family server: updates on, a non-root user with sudo, SSH keys only, a firewall… Beginner · Step by step · Linux Article Server hardening · Users, sudo & hardening 15 Oct 2026
0356 Free HTTPS with Let’s Encrypt and certbot Install certbot, get a trusted certificate for your domain and let it configure nginx or Apache, or just obtain the files for… Beginner · Step by step · Linux Article TLS & certificates 15 Oct 2026
0357 Keep secrets out of git: .env files, gitignore and what to do after a leak Load passwords and API keys from an untracked .env file, commit a safe .env.example instead, catch mistakes before they are pushed, and… Beginner · Step by step · Any system Article Housekeeping · Secrets & access 15 Oct 2026
0371 Where are the logs? journalctl, /var/log and container logs A practical map of where Linux programs write their logs and the commands to read them: journalctl filters, the classic files under… Beginner · Step by step · Linux Article Logs 15 Oct 2026
0372 Grafana: your first dashboard from Prometheus data Connect Grafana to a Prometheus server, build a four-panel host dashboard with PromQL queries, set units and thresholds, add an instance variable,… Beginner · Step by step · Browser, Linux, macOS Article Prometheus & Grafana 15 Oct 2026
0328 Install Docker Engine on Ubuntu and Debian Set up Docker's official apt repository, install Docker Engine with the Compose and Buildx plugins, run hello-world and let your user run… Beginner · Step by step · Linux Article Docker basics · Packages & updates 15 Oct 2026
0342 Which process is using a port, and how to free it Find the program behind a busy port with ss, lsof or fuser, decide whether to stop it properly or kill it, and… Beginner · Step by step · Linux, macOS Article DNS, IP addresses & ports · Networking & firewalls 15 Oct 2026
0202 Back up and restore PostgreSQL with pg_dump, pg_restore and pg_dumpall Make logical backups of one database with pg_dump, of roles and the whole cluster with pg_dumpall, and restore them with pg_restore or… Beginner · Step by step · Linux Article Backup & restore 15 Oct 2026
0214 MySQL users and privileges: CREATE USER, GRANT and authentication plugins A MySQL account is a user name plus the host it connects from. You create it with CREATE USER, give it rights… Beginner · Step by step · Linux Article Administration · Security & access 15 Oct 2026
0198 Install PostgreSQL and connect with psql on Debian, Ubuntu and RHEL Install the PostgreSQL server from your distribution or the official PGDG repositories, start it, and open your first psql session as the… Beginner · Step by step · Linux Article Install & connect 15 Oct 2026
0150 Logging in with oc and working with OpenShift projects Install the oc client, log in with a password, browser or token, then create, switch and inspect projects. Covers where oc stores… Beginner · Step by step · Any system Article Concepts · Deploying applications 15 Oct 2026
0151 Tutorial: deploy a small web app on OpenShift and expose it with a Route A step-by-step first deployment: create a project, build a static website from Git with Source-to-Image, publish it on an HTTPS Route, then… Beginner · Step by step · Any system Article Deploying applications 15 Oct 2026
0135 Deploy your first app on Kubernetes A step-by-step tutorial: write a Deployment and a Service in YAML, apply them, reach the app, add health probes, roll out a… Beginner · Step by step · Linux Article Ingress & networking · Workloads & services 15 Oct 2026
0101 Create LXC containers with pct and pveam Download a container template with pveam, create an unprivileged LXC container with pct, give it a network address and get a shell… Beginner · Step by step · Linux Article VMs & containers 15 Oct 2026
0099 Proxmox VE repositories and updates: enterprise vs no-subscription A fresh Proxmox VE install uses the enterprise repository, which needs a subscription. Learn how to switch to the no-subscription repository and… Beginner · Step by step · Linux Article Installation & first steps · Packages & updates 15 Oct 2026
0038 The pull request workflow on GitHub A pull request asks to merge your branch into another one, with review and automated checks in between. This is the whole… Beginner · Step by step · Any system Article Pull requests 15 Oct 2026
0053 Set up SSH keys: ssh-keygen, ssh-copy-id and ~/.ssh/config SSH keys let you log in to servers and push to Git hosts without typing a password. Create an ed25519 key, install… Beginner · Step by step · Linux, macOS, Windows Article Keys & config 15 Oct 2026
0067 Your first SQL queries: SELECT, WHERE, ORDER BY, LIMIT and GROUP BY Read data from a table, keep only the rows you want, sort them, take the first few, and summarize groups with COUNT,… Beginner · Step by step · Any system Article Queries 15 Oct 2026