Deploying a Containerized Backend to a VPS with Docker Compose + GitHub Actions (A Beginner's Runbook)

A complete, real-world guide to deploying a backend app on a single Linux VPS using Docker Compose and GitHub Actions. Covers multi-stage Dockerfiles, a full production Compose stack with Postgres, Redis, and pgbouncer, and a CI/CD pipeline that builds, scans, and deploys over SSH — plus a detailed breakdown of common errors most guides skip.