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Run PostgreSQL locally without installing the server: define one PostgreSQL service in Docker Compose, persist its files in a named volume, and use a Makefile to make routine commands easy to remember. Bind the published port to 127.0.0.1 if only programs on your computer need to connect. The database container can be replaced; the named volume is what keeps its data.
Set up one PostgreSQL container with Compose
Create compose.yaml in your project root. This PostgreSQL 18 example uses a named volume, publishes the database only on the local machine, and reads its password from the environment:
services:
db:
image: postgres:18
restart: unless-stopped
environment:
POSTGRES_USER: ${POSTGRES_USER:-postgres}
POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:?Set POSTGRES_PASSWORD in .env}
POSTGRES_DB: ${POSTGRES_DB:-postgres}
ports:
- "127.0.0.1:5432:5432"
volumes:
- postgres_data:/var/lib/postgresql
volumes:
postgres_data:Docker’s PostgreSQL guide uses the postgres:18 image and mounts storage at /var/lib/postgresql. For PostgreSQL 18 and later, the official image uses version-specific subdirectories beneath that parent path. Do not blindly reuse the older /var/lib/postgresql/data mount convention with these images; see the PostgreSQL Docker Official Image documentation.
Create a local .env file with values for POSTGRES_PASSWORD, POSTGRES_USER, and POSTGRES_DB. Keep real credentials out of version control; add .env to .gitignore if it is not already excluded. Compose substitutes these values when it reads the file. The image requires POSTGRES_PASSWORD for normal initialization; the user and database settings are optional and have defaults. These settings initialize a new database, not an existing one.
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Why choose a named volume?
The declared postgres_data volume stores database files independently of the container. Compose creates it if needed and reuses it on later starts. Removing or recreating the container therefore does not, by itself, erase the database. Docker describes named volumes as the simpler choice for most cases; a bind mount is an alternative when you specifically need files at a host path, but host permissions and ownership can complicate it. See Docker’s volume documentation.
Why bind the port to loopback?
The mapping 127.0.0.1:5432:5432 lets host-run tools such as psql and GUI clients reach the database at localhost:5432 without publishing it on other network interfaces. Docker’s guide recommends loopback binding for a development database meant for the same host. Remove the loopback restriction only when you have a specific need for access from elsewhere and understand the exposure.
Put repeatable commands in a Makefile
A Makefile can serve as a short interface for starting, inspecting, connecting to, and stopping the service. Add this as Makefile alongside compose.yaml:
.PHONY: help up down status logs psql reset
help:
@printf '%sn'
'up Start PostgreSQL'
'down Stop and remove the container; keep database data'
'status Show Compose services'
'logs Follow PostgreSQL logs'
'psql Open psql inside the container'
'reset DESTRUCTIVE: remove the container and database volume'
up:
docker compose up -d
down:
docker compose down
status:
docker compose ps
logs:
docker compose logs -f db
psql:
docker compose exec db psql -U "$${POSTGRES_USER:-postgres}" -d "$${POSTGRES_DB:-postgres}"
reset:
docker compose down -vMake recipes must begin with a tab. Run make help to see the available targets, then use make up to start the service. make psql runs the client inside the database container; a host-installed psql or GUI client can instead connect to host localhost, port 5432, using the database and credentials from .env.
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Check readiness before connecting
docker compose up -d starts the container in the background, but a running container is not necessarily ready to accept database connections. Docker states that “On startup, Compose does not wait until a container is ‘ready’, only until it’s running.” For a person connecting from the host, check status or retry the connection after startup; make logs can help show what the database is doing.
For a repeatable readiness check, add this service configuration under db in compose.yaml:
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healthcheck:
test: ["CMD-SHELL", "pg_isready -U $${POSTGRES_USER} -d $${POSTGRES_DB}"]
interval: 5s
timeout: 5s
retries: 5Then docker compose ps reports health as well as service state. The double dollar signs defer variable expansion to the container. This healthcheck is useful even in a one-service setup, but it becomes especially important if you later add a containerized application: configure that app’s dependency on db with condition: service_healthy. Compose’s startup-order documentation explains the readiness condition and pg_isready approach.
Know what persists—and what reset deletes
Changing POSTGRES_PASSWORD, POSTGRES_USER, POSTGRES_DB, or an initialization script does not reconfigure a database that has already been initialized in the volume. The official image’s initialization behavior applies when the data directory is empty; an existing database is left in place on subsequent starts. Change an existing database using PostgreSQL itself, or reset only when you deliberately want a fresh, empty database.
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make down stops and removes Compose’s containers while retaining the named volume. make reset runs docker compose down -v, which also removes the volume and deletes its database data. Export anything you need before using it. Docker documents this distinction in its volume guidance and PostgreSQL guide.
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