Secrets Buildkite Plugin

A Buildkite plugin to fetch secrets from multiple providers and inject them into your build environment.

Supported providers:

• Buildkite Secrets (default)
• GCP Secret Manager
• Azure Key Vault

Changes to consider when upgrading to v2.0.0

If upgrading from v1.x.x, note these changes:

• Log format: Uses structured prefixes ([INFO], [WARNING], [ERROR]) instead of emoji
• Removed: dump_env function removed for security
• New default: Secrets auto-redacted from logs (requires agent v3.67.0+). Opt out with skip-redaction: true
• Stricter errors: Invalid base64-encoded secrets now fail immediately

Buildkite Secrets Provider (Default)

The default provider fetches secrets from Buildkite Secrets.

You can create a secret in your Buildkite cluster(s) from the Buildkite UI following the instructions in the documentation here.

Individual Variables

Create a Buildkite secret for each variable that you need to store. Paste the value of the secret into buildkite.com directly.

A pipeline.yml like this will read each secret out into an environment variable:

steps:
  - command: echo "The content of ANIMAL is \$ANIMAL"
    plugins:
      - secrets#v2.1.0:
          variables:
            ANIMAL: llamas
            FOO: bar

Batch Secrets (Base64)

Create a single Buildkite secret with one variable per line, encoded as base64 for storage.

For example, setting three variables looks like this in a file:

Foo=bar
SECRET_KEY=llamas
COFFEE=more

Then encode the file:

cat data.txt | base64

Next, upload the base64 encoded data to buildkite.com in your browser with a key of your choosing - like llamas. The three secrets can be read into the job environment using a pipeline.yml like this:

steps:
  - command: build.sh
    plugins:
      - secrets#v2.1.0:
          env: "llamas"

GCP Secret Manager Provider

Fetches secrets from GCP Secret Manager.

Prerequisites

• The gcloud CLI must be installed and available on the Buildkite agent.
• The agent must be authenticated to GCP with permissions to access Secret Manager (e.g., the roles/secretmanager.secretAccessor role). For Buildkite-hosted agents, use the gcp-workload-identity-federation plugin to authenticate.
• The Secret Manager API must be enabled on the GCP project.

GCP Project Configuration

The GCP project is resolved in this order:

1. The gcp-project plugin option
2. The CLOUDSDK_CORE_PROJECT environment variable
3. The active gcloud config project (gcloud config get-value project)

Individual Variables

Create secrets in GCP Secret Manager, then map them to environment variables:

steps:
  - command: build.sh
    plugins:
      - gcp-workload-identity-federation#v1.5.0:
          audience: "//iam.googleapis.com/projects/123456789/locations/global/workloadIdentityPools/my-pool/providers/buildkite"
          service-account: "my-service-account@my-project-id.iam.gserviceaccount.com"
      - secrets#v2.1.0:
          provider: gcp
          gcp-project: my-project-id
          variables:
            API_KEY: my-api-key-secret
            DB_PASSWORD: my-db-password-secret

Each key under variables becomes the environment variable name, and the value is the GCP secret ID to fetch.

Batch (Base64-Encoded)

Store multiple KEY=value pairs in a single GCP secret, base64-encoded:

# Create a file with your variables
cat > secrets.txt <<EOF
API_KEY=sk-abc123
DB_HOST=db.example.com
DB_PASSWORD=supersecret
EOF

# Base64-encode and store in GCP Secret Manager
base64 secrets.txt | gcloud secrets create ci-env-secrets --data-file=-

Then reference the secret in your pipeline:

steps:
  - command: build.sh
    plugins:
      - gcp-workload-identity-federation#v1.5.0:
          audience: "//iam.googleapis.com/projects/123456789/locations/global/workloadIdentityPools/my-pool/providers/buildkite"
          service-account: "my-service-account@my-project-id.iam.gserviceaccount.com"
      - secrets#v2.1.0:
          provider: gcp
          gcp-project: my-project-id
          env: "ci-env-secrets"

Azure Key Vault Provider

Use provider: azure to fetch secrets from Azure Key Vault.

Prerequisites

• Azure CLI (az) installed on your Buildkite agent
• The agent must be authenticated to Azure. Use the azure-login plugin to authenticate via managed identity or service principal.
• The authenticated identity must have the Key Vault Secrets User role (or equivalent get permission) on the vault

Configuration

Set provider: azure and azure-vault-name in your plugin configuration:

steps:
  - command: build.sh
    plugins:
      - azure-login#v1.0.1:
          client-id: "your-client-id"
          tenant-id: "your-tenant-id"
      - secrets#v2.1.0:
          provider: azure
          azure-vault-name: my-vault
          variables:
            API_KEY: my-api-key-secret

Individual Variables

Each key in variables maps to an Azure Key Vault secret name. The secret's value is fetched and exported as the corresponding environment variable:

steps:
  - command: build.sh
    plugins:
      - azure-login#v1.0.1:
          client-id: "your-client-id"
          tenant-id: "your-tenant-id"
      - secrets#v2.1.0:
          provider: azure
          azure-vault-name: my-vault
          variables:
            DB_PASSWORD: db-password
            API_TOKEN: api-token
            SSH_KEY: deploy-ssh-key

Azure Key Vault secret names must contain only alphanumeric characters and hyphens, and must start with an alphanumeric character.

Batch Secrets (Base64)

Store multiple KEY=value pairs as a single base64-encoded Azure Key Vault secret, then use env to fetch and decode them all at once:

steps:
  - command: build.sh
    plugins:
      - azure-login#v1.0.1:
          client-id: "your-client-id"
          tenant-id: "your-tenant-id"
      - secrets#v2.1.0:
          provider: azure
          azure-vault-name: my-vault
          env: batch-secrets

To create the batch secret:

# Create a file with KEY=value pairs
cat > data.txt <<EOF
DB_HOST=mydb.example.com
DB_PASSWORD=supersecret
API_KEY=abc123
EOF

# Base64 encode and store in Azure Key Vault
az keyvault secret set --vault-name my-vault --name batch-secrets --value "$(base64 < data.txt)"

Combining Both Methods

You can use env and variables together to fetch both batch and individual secrets in a single plugin call.

GCP:

steps:
  - command: build.sh
    plugins:
      - gcp-workload-identity-federation#v1.5.0:
          audience: "//iam.googleapis.com/projects/123456789/locations/global/workloadIdentityPools/my-pool/providers/buildkite"
          service-account: "my-service-account@my-project-id.iam.gserviceaccount.com"
      - secrets#v2.1.0:
          provider: gcp
          gcp-project: my-project-id
          env: "ci-env-secrets"
          variables:
            DEPLOY_KEY: deploy-key-secret

Azure:

steps:
  - command: build.sh
    plugins:
      - azure-login#v1.0.1:
          client-id: "your-client-id"
          tenant-id: "your-tenant-id"
      - secrets#v2.1.0:
          provider: azure
          azure-vault-name: my-vault
          env: batch-secrets
          variables:
            DEPLOY_KEY: deploy-key-secret

Pinning a Secret Version (GCP)

By default, the latest version of each secret is fetched. To pin to a specific version:

steps:
  - command: build.sh
    plugins:
      - gcp-workload-identity-federation#v1.5.0:
          audience: "//iam.googleapis.com/projects/123456789/locations/global/workloadIdentityPools/my-pool/providers/buildkite"
          service-account: "my-service-account@my-project-id.iam.gserviceaccount.com"
      - secrets#v2.1.0:
          provider: gcp
          gcp-project: my-project-id
          gcp-secret-version: "5"
          variables:
            API_KEY: my-api-key-secret

Pinning a Secret Version (Azure)

By default, the latest version of each secret is fetched. To pin to a specific version:

steps:
  - command: build.sh
    plugins:
      - azure-login#v1.0.1:
          client-id: "your-client-id"
          tenant-id: "your-tenant-id"
      - secrets#v2.1.0:
          provider: azure
          azure-vault-name: my-vault
          azure-secret-version: "a1b2c3d4e5f6"
          variables:
            API_KEY: my-api-key

Options

Common Options

These options apply to all providers.

Option	Type	Default	Description
provider	string	buildkite	The secrets provider to use. Supported values: buildkite, gcp, azure.
env	string	-	Secret key name for fetching batch secrets (base64-encoded KEY=value format).
variables	object	-	Map of ENV_VAR_NAME: secret-path pairs to inject as environment variables.
skip-redaction	boolean	false	If true, secrets will not be automatically redacted from logs.
retry-max-attempts	number	5	Maximum retry attempts for transient failures.
retry-base-delay	number	2	Base delay in seconds for exponential backoff between retries.

GCP Provider Options

These options only apply when provider: gcp is set.

Option	Type	Default	Description
gcp-project	string	-	GCP project ID. Falls back to CLOUDSDK_CORE_PROJECT or gcloud config.
gcp-secret-version	string	latest	The secret version to fetch.

Azure Provider Options

These options only apply when provider: azure is set.

Option	Type	Default	Description
azure-vault-name	string	-	The Azure Key Vault name (required when provider is azure).
azure-secret-version	string	latest	The secret version to fetch. If not specified, the latest version is used.

Secret Redaction

By default, this plugin automatically redacts all fetched secrets from your Buildkite logs to prevent accidental exposure. This includes:

• The raw secret values
• Shell-escaped versions of secrets
• Base64-decoded versions of secrets (if the secret appears to be base64-encoded)

The redaction feature uses the buildkite-agent redactor add command, which requires buildkite-agent v3.67.0 or later. If you're running an older version, the plugin will log a warning and continue without redaction.

To disable automatic redaction (not recommended), set skip-redaction: true:

steps:
  - command: build.sh
    plugins:
      - secrets#v2.1.0:
          env: "llamas"
          skip-redaction: true

Retry Behavior

This plugin implements automatic retry logic with exponential backoff for secret calls. This will occur for 5xx server errors or any local network issues. If a 4xx code is received, a fast failure will be served.

By default, the base delay will be 2 seconds, with a maximum of 5 retries.

Example with Custom Retry

steps:
  - command: build.sh
    plugins:
      - secrets#v2.1.0:
          env: "llamas"
          retry-max-attempts: 10
          retry-base-delay: 2

Testing

You can run the tests using docker-compose:

docker compose run --rm tests

License

MIT (see LICENSE)