> ## Documentation Index
> Fetch the complete documentation index at: https://namespace.so/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Optimizing Docker Build Performance in Circle CI

Namespace provides high-performance Remote Builders that can significantly speed up your Docker builds in CircleCI workflows.
The easiest way to use Namespace Remote Builders is through the `namespacelabs/build` orb, which handles all the configuration automatically.

## Access to Namespace

Namespace federates with CircleCI using [OpenID Connect](https://circleci.com/docs/openid-connect-tokens/) to generate short-lived access tokens.

After a one-time setup, your workflows can access Namespace indefinitely, without relying on pre-shared keys which can be more easily compromised:

1. **Find your CircleCI Organization ID** in [Organization Settings > Overview](https://app.circleci.com/settings/organization) in the CircleCI web application.
2. **Email support** at [support@namespace.so](mailto:support@namespace.so) with both your Organization ID and your Namespace workspace ID from the [Dashboard](https://cloud.namespace.so/workspace/settings).

## Using Remote Builders

<Steps titleSize="h3">
  <Step title="Add the orb to your CircleCI configuration">
    ```yaml theme={null}
    orbs:
      build: namespacelabs/build@0.2.1
    ```
  </Step>

  <Step title="Configure the Namespace Remote Builder environment">
    ```yaml {3} theme={null}
    steps:
      - checkout
      - build/setup
    ```
  </Step>

  <Step title="Use the Remote Builder">
    When invoking `docker build`, pass `namespace` as `--builder` to `buildx`:

    ```bash theme={null}
    docker buildx build --builder namespace .
    ```
  </Step>
</Steps>

## Complete example

```yaml theme={null}
version: 2.1

orbs:
  build: namespacelabs/build@0.2.1

jobs:
  docker-build:
    docker:
      - image: cimg/base:stable
    steps:
      - checkout
      - build/setup
      - run:
          name: Build and push Docker image
          command: |
            docker buildx build --builder namespace .

workflows:
  build:
    jobs:
      - docker-build
```