Examples

Simple service graph

db:
  _type: "myapp.db.Database"
  host: "localhost"
  port: 5432

cache:
  _type: "myapp.cache.RedisCache"
  url: "redis://localhost:6379"

service:
  _type: "myapp.services.UserService"
  db: { _ref: "db" }
  cache: { _ref: "cache" }

from sygaldry import Artificery

graph = Artificery("config.yaml").resolve()
service = graph["service"]

Includes with overrides

# base.yaml
service:
  host: "localhost"
  port: 9000

# prod.yaml
_include:
  - base.yaml
service:
  port: 9001

Interpolation and refs

db:
  _type: "myapp.db.Database"
  host: "${DB_HOST:-localhost}"
  port: 5432

url: "postgres://${db.host}:${db.port}/app"

Dict keys via _entries

key:
  _type: "myapp.models.Key"
  name: "primary"

map:
  _entries:
    - _key: { _ref: "key" }
      _value: 123

Static type checking

Given the service graph above, run a type checker to catch wiring errors before any objects are instantiated:

sygaldry check -c config.yaml

The checker generates equivalent Python constructor calls and passes them to ty, basedpyright, pyright, or mypy. If UserService.__init__ expects a PostgresDB but db resolves to a Database, the type checker will report the mismatch against the service config path.