Serialization

The Docker lexicon serializes to two output formats.

docker-compose.yml

chant build src --lexicon docker -o docker-compose.yml

Each entity type maps to a top-level Compose section. The TypeScript export name becomes the key within that section.

export const db = new Service({ image: "postgres:16-alpine" });
export const pgdata = new Volume({});
export const backend = new Network({ driver: "bridge" });

Produces:

services:
  db:
    image: postgres:16-alpine

volumes:
  pgdata: null

networks:
  backend:
    driver: bridge

defaultLabels() entities are not emitted as separate keys — their labels are merged into each service.

Dockerfile.{name}

chant build src --lexicon docker
# Writes Dockerfile.app, Dockerfile.builder, etc.

Each Dockerfile entity produces a separate file. The export name is the suffix.

export const builder = new Dockerfile({ from: "node:20-alpine", ... });
// → Dockerfile.builder

Field mapping

TypeScript	docker-compose.yml	Notes
env("X", { required: true })	${X:?X is required}	Compose interpolation
env("X", { default: "v" })	${X:-v}	Compose interpolation
env("X")	${X}	Compose interpolation
external: true	external: true	Volume/Network

Specifying lexicon at build time

The --lexicon docker flag restricts output to Docker entities only — useful in mixed-lexicon projects:

# Only Docker output
chant build src --lexicon docker -o docker-compose.yml

# Other lexicons still get their own outputs
chant build src --lexicon aws -o template.json