switchboard.yaml

The project config file: every field, plus environment variable expansion and the S3 credential variables.

switchboard.yaml lives at the root of a rule project (written by switchboard init) and supplies defaults for every CLI command, so day-to-day work needs no flags. Any flag overrides its config counterpart.

name: my-rules
rule: ./rules/basic
dist: ./dist
namespace: customer-a
channel: prod
registry: file://./registry

Fields

Field	Required	Description
`name`	yes	Project and bundle name.
`rule`	yes	Path to the rule package `switchboard build` compiles.
`dist`	yes	Bundle output directory; also the default ref for `test`, `eval`, and `replay --candidate`.
`tests`	no	Path to the `tests.yaml` embedded at build time. Defaults to the `tests.yaml` next to the rule package.
`data`	no	Directory of read-only data files embedded at build time. Defaults to the `data/` directory next to the rule package.
`max_data_bytes`	no	Maximum total size of embedded data files (e.g. `8mb`). Defaults to 4mb.
`namespace`	no	Registry namespace for tenant isolation.
`channel`	yes	Default deploy channel.
`registry`	no	Registry URL; see Registries for the schemes.

Environment variable expansion

Environment variables are expanded before the YAML is parsed, in all of these forms:

registry: s3://rules/${ENVIRONMENT}
channel: ${CHANNEL:-prod}        # fallback when unset or empty
namespace: ${TENANT-shared}      # fallback when unset

$VAR and ${VAR}: simple substitution
${VAR:-fallback}: fallback when the variable is unset or empty
${VAR-fallback}: fallback only when the variable is unset

This makes one switchboard.yaml serve every environment; CI selects the channel and registry through its environment.

Environment variables

S3 registry credentials

Used by any command touching an s3:// registry:

Variable	Description
`SWITCHBOARD_S3_ENDPOINT`	S3 endpoint host, e.g. `localhost:9000` or `s3.amazonaws.com`.
`SWITCHBOARD_S3_ACCESS_KEY`	Access key.
`SWITCHBOARD_S3_SECRET_KEY`	Secret key.
`SWITCHBOARD_S3_BUCKET`	Bucket name.
`SWITCHBOARD_S3_INSECURE`	`true` to use plain HTTP (local MinIO).

Deployer identity

deploy, promote, and rollback record who acted, resolving the first of:

SWITCHBOARD_DEPLOYER
GITHUB_ACTOR (set automatically in GitHub Actions)
$USER