---
title: Building with Bake from a Compose file
description: Build your compose services with Bake
keywords: build, buildx, bake, buildkit, compose, yaml
aliases:
  - /build/customize/bake/compose-file/
---

Bake supports the [Compose file format](/reference/compose-file/_index.md)
to parse a Compose file and translate each service to a [target](reference.md#target).

```yaml
# compose.yaml
services:
  webapp-dev:
    build: &build-dev
      dockerfile: Dockerfile.webapp
      tags:
        - docker.io/username/webapp:latest
      cache_from:
        - docker.io/username/webapp:cache
      cache_to:
        - docker.io/username/webapp:cache

  webapp-release:
    build:
      <<: *build-dev
      x-bake:
        platforms:
          - linux/amd64
          - linux/arm64

  db:
    image: docker.io/username/db
    build:
      dockerfile: Dockerfile.db
```

```console
$ docker buildx bake --print
```

```json
{
  "group": {
    "default": {
      "targets": ["db", "webapp-dev", "webapp-release"]
    }
  },
  "target": {
    "db": {
      "context": ".",
      "dockerfile": "Dockerfile.db",
      "tags": ["docker.io/username/db"]
    },
    "webapp-dev": {
      "context": ".",
      "dockerfile": "Dockerfile.webapp",
      "tags": ["docker.io/username/webapp:latest"],
      "cache-from": [
        {
          "ref": "docker.io/username/webapp:cache",
          "type": "registry"
        }
      ],
      "cache-to": [
        {
          "ref": "docker.io/username/webapp:cache",
          "type": "registry"
        }
      ]
    },
    "webapp-release": {
      "context": ".",
      "dockerfile": "Dockerfile.webapp",
      "tags": ["docker.io/username/webapp:latest"],
      "cache-from": [
        {
          "ref": "docker.io/username/webapp:cache",
          "type": "registry"
        }
      ],
      "cache-to": [
        {
          "ref": "docker.io/username/webapp:cache",
          "type": "registry"
        }
      ],
      "platforms": ["linux/amd64", "linux/arm64"]
    }
  }
}
```

The compose format has some limitations compared to the HCL format:

- Specifying variables or global scope attributes is not yet supported
- `inherits` service field is not supported, but you can use [YAML anchors](/reference/compose-file/fragments.md)
  to reference other services, as demonstrated in the previous example with `&build-dev`.

## `.env` file

You can declare default environment variables in an environment file named
`.env`. This file will be loaded from the current working directory,
where the command is executed and applied to compose definitions passed
with `-f`.

```yaml
# compose.yaml
services:
  webapp:
    image: docker.io/username/webapp:${TAG:-v1.0.0}
    build:
      dockerfile: Dockerfile
```

```sh
# .env
TAG=v1.1.0
```

```console
$ docker buildx bake --print