How-to guides
Practical articles for developers — workflows, tooling, and techniques you can use today. Each guide is organized with clear headings, context for why steps matter, and copy-paste commands where it helps.
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How to Take a Screenshot on Mac
Productivity & workflows Beginner 3 min read
Use built-in keyboard shortcuts and Screenshot.app to capture the full screen, a window, or any region.
Step-by-step guide to screenshots on Mac: Command+Shift+3/4/5, selection and window capture, copy to clipboard with Control, and default save location.
Developer Productivity: Shell Aliases, Functions, and Tiny Scripts
Productivity & workflows Beginner 2 min read
Automate boring terminal work: safe aliases, parameterized functions, and one-file scripts you can commit to dotfiles.
Speed up the terminal: aliases vs functions, Git/Docker one-liners, dotfile organization, and when to reach for Make or a real task runner.
GitHub Actions CI for Developers: Workflows, Secrets, and Caching
DevOps & infrastructure Intermediate 2 min read
Run tests on every push: YAML structure, matrix builds, encrypted secrets, and faster pipelines with cache.
Set up GitHub Actions: build and test on push, use secrets safely, cache dependencies, and mirror patterns from Git best practices.
Python Pandas for Data Analysis: A Practical Intro
Data & machine learning Beginner 2 min read
Load CSVs, explore DataFrames, filter and group data, and export results—ideal after you have Python installed.
Learn pandas: load tabular data, filter rows, aggregate with groupby, join tables, handle NaNs, and move toward reproducible notebooks.
RAG for Developers: Retrieval-Augmented Generation Explained
AI & LLMs Intermediate 2 min read
Add documents to an LLM’s context safely: chunking, embeddings, vector search, and evaluation—without hand-waving.
Learn RAG: chunk documents, embed text, query a vector store, feed grounded context to an LLM, and avoid hallucinations with citations and evals.
nginx Reverse Proxy and TLS: Upstreams, Headers, and Let’s Encrypt
DevOps & infrastructure Advanced 2 min read
Put nginx in front of your app with proxy_pass, forward client metadata, redirect HTTP to HTTPS, and outline Certbot for free certificates.
Configure nginx reverse proxy with proxy_pass, trusted headers, HTTP to HTTPS, and a high-level Let’s Encrypt / Certbot flow for real servers.
Docker Compose Tutorial: App + Database + Persistent Volumes
DevOps & infrastructure Intermediate 2 min read
Model a small dev stack in docker-compose.yml: web service, Postgres, networks, env files, and healthchecks.
Build a docker-compose.yml with app and database, persistent volumes, networks, env files, and healthchecks—links to Docker install and SQL basics.
How to Install Docker on Linux and Run Your First Container
DevOps & infrastructure Intermediate 2 min read
Install Docker Engine from official repos, add your user to the docker group, and run hello-world plus a useful database image.
Install Docker Engine on Linux, fix permission denied with the docker group, run your first container, understand images and volumes, preview Docker Compose.
Environment Variables & Secrets: .env, Twelve-Factor, and Safe Defaults
Security & secrets Intermediate 2 min read
Separate config from code, ship .env.example, wire CI secrets, and never commit API keys—plus what to do if you leak one.
Use .env and environment variables safely: twelve-factor apps, .env.example, CI secrets, rotation, and pairing with Git hygiene when credentials leak.
REST API Tutorial: HTTP Methods, Status Codes, Headers, and curl
APIs & HTTP Intermediate 3 min read
Call REST APIs with confidence: verbs, common status codes, auth headers, and quick tests from the terminal.
Learn REST: HTTP methods, status codes, headers, JSON bodies, Bearer auth, pagination, and how to test endpoints with curl from your terminal.
SSH Keys for GitHub and GitLab: Generate, Add, and Fix Permission Denied
Security & secrets Intermediate 3 min read
Create an ed25519 key, load it in ssh-agent, add the public key to your host, and debug common auth failures.
Step-by-step SSH keys for Git: ed25519, ssh-agent, GitHub/GitLab settings, known_hosts, and debugging Permission denied when pushing or pulling.
How to Install Node.js and npm: nvm, fnm, and Fix Permission Errors
Languages & runtimes Beginner 3 min read
Use an LTS Node version, switch runtimes with nvm or fnm, and stop EACCES errors when installing global packages.
Install Node.js and npm, use nvm or fnm for version switching, understand package.json and lockfiles, and resolve npm EACCES and permission issues.