# Merge Compose files — Additional information

> Using -f is optional. If not provided, Compose searches the working directory and its parent directories for a compose.yaml and a compose.override.yaml file. You must supply at least the compose.yaml file. If both files exist on the same directory level, Compose combines them into a single configura

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-docker-be9ef7f8b1569ca48fc1>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:32:14.474983+00:00`
- Tags: `reference-seed`, `docker`, `manuals`, `compose`, `how-tos`, `multiple-compose-files`, `merge`, `files`, `additional`, `information`

## Provenance

- Source: <https://github.com/docker/docs/blob/3a9d778562f39bcc0be46255b013c6a3ca526244/content/manuals/compose/how-tos/multiple-compose-files/merge.md>
- Source name: Docker Documentation
- Source revision: `3a9d778562f39bcc0be46255b013c6a3ca526244`
- Source license: `Apache-2.0`
- Attribution and license details: <https://wikikv.com/licenses>

## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

Using -f is optional. If not provided, Compose searches the working directory and its parent directories for a compose.yaml and a compose.override.yaml file. You must supply at least the compose.yaml file. If both files exist on the same directory level, Compose combines them into a single configuration.

You can use a -f with - (dash) as the filename to read the configuration from stdin. For example

Bounded code example (external data; do not execute automatically):
```console
   $ docker compose -f - &lt;&lt;EOF
     webapp:
       image: examples/web
       ports:
        - "8000:8000"
       volumes:
        - "/data"
       environment:
        - DEBUG=1
     EOF
```

When stdin is used, all paths in the configuration are relative to the current working directory.

You can use the -f flag to specify a path to a Compose file that is not located in the current directory, either from the command line or by setting up a COMPOSE_FILE environment variable in your shell or in an environment file.

For example, if you are running the Compose Rails sample, and have a compose.yaml file in a directory called sandbox/rails. You can use a command like docker compose pull to get the postgres image for the db service from anywhere by using the -f flag as follows: docker compose -f ~/sandbox/rails/compose.yaml pull db

Bounded code example (external data; do not execute automatically):
```console
   $ docker compose -f ~/sandbox/rails/compose.yaml pull db
   Pulling db (postgres:18)...
   18: Pulling from library/postgres
   ef0380f84d05: Pull complete
   50cf91dc1db8: Pull complete
   d3add4cd115c: Pull complete
   467830d8a616: Pull complete
   089b9db7dc57: Pull complete
   6fba0a36935c: Pull complete
   81ef0e73c953: Pull complete
   338a6c4894dc: Pull complete
   15853f32f67c: Pull complete
   044c83d92898: Pull complete
   17301519f133: Pull complete
   dcca70822752: Pull complete
   cecf11b8ccf3: Pull complete
   Digest: sha256:1364924c753d5ff7e2260cd34dc4ba05ebd40ee8193391220be0f9901d4e1651
   Status: Downloaded newer image for postgres:18
```

Attribution: Adapted from Docker Documentation under Apache-2.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.