Orientation brief

Docker Compose

Up until now, you've been working with individual containers. Run nginx. Run postgres. Connect them manually. Manage each one separately. But real applications aren't single containers. They're systems. A typical web application has: - A web server (nginx) - An application server (Node.js, Python, Go) - A database (PostgreSQL, MySQL) - A cache (Redis) - A message queue (RabbitMQ) - Maybe background workers Starting these containers one by one, configuring their networks, managing their volumes, ensuring they start in the right order, passing environment variables—it becomes unwieldy fast. You end up with a shell script full of `docker run` commands. Each command is 10 lines long with flags for networks, volumes, environment variables, port mappings. It's fragile. It's hard to share. It's error-prone. **Docker Compose solves this.** Compose lets you define your entire multi-container application in a single YAML file. One command starts everything. One command stops everything. The configuration is declarative, readable, and version-controlled. By the end of this module, you'll understand: - What problems Docker Compose solves - How to write docker-compose.yml files - How to orchestrate multi-container applications - How services, networks, and volumes work together - How to manage configuration and secrets - Development workflows with Compose

Understand the problem this module is here to solve.

Read 6 chapters in order, from context to application.

Practice the module concepts through focused exercises.

Chapter route

Read in order

Practice

Module exercises

Move from reading to investigation with scenario-based practice for this module.

Open exercises →