Advanced Topics

Networking

All containers share a single Docker network called dde. Containers communicate via service names — a web container reaches MariaDB at mariadb:3306, Valkey at valkey:6379, and Mailpit SMTP at mail:1025.

DNS resolution for *.test domains is handled by a dnsmasq container that resolves everything to 127.0.0.1. On macOS this uses /etc/resolver/test, on Linux it integrates with systemd-resolved or NetworkManager. All configured automatically by dde system:install.

TLS Certificates

dde uses mkcert for locally-trusted HTTPS. system:install creates a root CA trusted by your OS and browsers. Certificates are generated per-project during project:up — no manual setup needed.

Multiple Projects

Multiple projects run simultaneously, each with a unique hostname (project-a.test, project-b.test). Traefik routes requests by hostname, so there are no port conflicts.

Database services are shared — a single MariaDB instance serves all projects, each using its own database (named after the project). If two projects need different versions, dde creates separate containers (dde-mariadb-10, dde-mariadb-11.8).

Stopping one project does not affect others. Use dde system:down to stop all services.

JSON Output

All commands support --output=json for scripting:

dde project:describe --output=json | jq -r '.data.hostname'

Response format:

{
    "status": "ok",
    "message": "",
    "data": { ... },
    "errors": []
}

Interactive commands (project:shell, project:logs --follow) do not support JSON output.