Docker Compose Generator
Describe your stack and get a working compose.yaml: your application, a database, Redis and helper tools, wired together with health checks, persistent volumes and passwords kept in a separate .env file. The passwords are generated in your browser.
- Runs in your browser
- No sign-up
- Free to use
Start it
How to use Docker Compose Generator
- Name your app service and choose whether to build it or use an existing image.
- Pick a database and tick any additional services.
- Choose the restart policy and whether to wait for healthy dependencies.
- Save compose.yaml and .env in your project folder and run the start command.
Docker Compose Generator features
Four databases
PostgreSQL, MySQL, MariaDB and MongoDB with the correct environment variables, data paths and health checks.
Start order that works
The app waits until the database and Redis report healthy, not merely started.
Secrets out of the file
Passwords are referenced as ${DB_PASSWORD} and generated into a .env file.
Persistent data
Named volumes keep the database across restarts and upgrades.
Development helpers
Adminer for browsing SQL databases and Mailpit for catching outgoing email, bound to localhost only.
Connection URL included
DATABASE_URL and REDIS_URL are passed to the app with the right host names and ports.
When to use Docker Compose Generator
- A local development environment that every team member starts with one command.
- Running an app with its database on a single server.
- Trying a database or cache without installing it on your machine.
- A starting point for integration tests in a pipeline.
Docker Compose Generator FAQ
What is the difference between a Dockerfile and compose.yaml?
A Dockerfile describes how to build one image. A Compose file describes how to run several containers together: which images, which ports, which volumes, which environment variables, and how they depend on each other. An application typically has one Dockerfile and one Compose file that refers to it.
Why does the app use “db” as the host name?
Compose creates a private network for the project and registers every service under its name. Inside that network, the database is reachable as db, on its normal port. “localhost” would refer to the app container itself, which is the most common mistake in connection settings.
Is my data lost when I stop the containers?
No. Data is stored in a named volume, which survives “docker compose down” and image upgrades. It is deleted only by “docker compose down -v” or by removing the volume explicitly.
Is the .env file safe?
It keeps passwords out of the Compose file, so that the file can be committed. The .env file itself must stay out of version control. For production on a shared platform, use Docker secrets or the secret store of your orchestrator.
Why are some ports bound to 127.0.0.1?
A published port is normally open on every network interface of the host, and Docker opens it in the firewall. Binding database and admin ports to 127.0.0.1 makes them reachable from the machine itself and from nowhere else.
docker-compose or docker compose?
The current tool is “docker compose”, a plugin of the Docker CLI. The older standalone “docker-compose” is no longer developed. The generated file follows the Compose Specification, uses the preferred file name compose.yaml and needs no version line.
Several containers, one description
Few applications consist of a single process. A typical web app needs a database, often a cache or queue, sometimes a mail server and a reverse proxy. Starting each container by hand with the right ports, networks, volumes and environment variables is error-prone. Compose puts the whole arrangement into one file, and a single command creates or removes it.
Three concepts carry most of the weight. Services are the containers and how each is configured. Networks connect them: by default, all services of a project share one network in which they find each other by service name. Volumes hold data that must outlive a container, such as the files of a database. Because containers are disposable and are replaced on every upgrade, anything that is not in a volume is lost when the container goes.
Start order is a classic difficulty. Declaring that the app depends on the database only ensures that the database container is started first, not that the database inside it is ready, which can take several seconds. A health check gives each service a test, such as pg_isready, and the condition service_healthy makes Compose wait for it. Applications should still retry failed connections, since a database can also restart later.
Compose is at its best for development environments and for small deployments on one host. The same file documents the stack for every developer, removes “works on my machine” differences and makes onboarding a matter of one command. For clusters of many machines, orchestrators such as Kubernetes take over, but the concepts of services, networks, volumes and health checks carry across unchanged.