# Building Compose projects with Bake — Customize the build group

> Start by redefining the default build group that Bake executes.

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-docker-1d61243436ed51690e4e>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:32:14.464221+00:00`
- Tags: `reference-seed`, `docker`, `guides`, `building`, `compose`, `projects`, `bake`, `customize`, `build`, `group`

## Provenance

- Source: <https://github.com/docker/docs/blob/3a9d778562f39bcc0be46255b013c6a3ca526244/content/guides/compose-bake.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).

Start by redefining the default build group that Bake executes. The current default group includes a seed target — a Compose service used solely to populate the database with mock data. Since this target doesn't produce a production image, it doesn't need to be included in the build group.

To customize the build configuration that Bake uses, create a new file at the root of the repository, alongside your compose.yaml file, named docker-bake.hcl.

Bounded code example (external data; do not execute automatically):
```console
$ touch docker-bake.hcl
```

Open the Bake file and add the following configuration

Bounded code example (external data; do not execute automatically):
```hcltitledocker-bake.hcl
group "default" {
  targets = ["vote", "result", "worker"]
}
```

Save the file and print your Bake definition again.

Bounded code example (external data; do not execute automatically):
```console
$ docker buildx bake --print
```

The JSON output shows that the default group only includes the targets you care about.

Bounded code example (external data; do not execute automatically):
```json
{
  "group": {
    "default": {
      "targets": ["vote", "result", "worker"]
    }
  },
  "target": {
    "result": {
      "context": "result",
      "dockerfile": "Dockerfile",
      "tags": ["username/result"]
    },
    "vote": {
      "context": "vote",
      "dockerfile": "Dockerfile",
      "tags": ["username/vote"],
      "target": "dev"
    },
    "worker": {
      "context": "worker",
      "dockerfile": "Dockerfile",
      "tags": ["username/worker"]
    }
  }
}
```

Here, the build configuration for each target (context, tags, etc.) is picked up from the compose.yaml file. The group is defined by the docker-bake.hcl file.

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.