Docker

The production stack is defined in docker-compose.yaml. The Caddy container is the entry point to the core platform: it publishes APP_PORT on the host and forwards API requests (/api/*) to the api container, file requests (/storage/*) to the rustfs container while file storage is enabled, and every other request to the web container, which serves the single-page app. The gateway publishes its own port, GATEWAY_PORT.

Services

Service	Purpose	Required
`caddy`	Entry point that routes requests to the other services	Yes
`api`	REST API	Yes
`web`	The web app clinicians and administrators use	Yes
`mongo`	Database	Yes
`gateway`	Serves remote assignments to participants	Only to send remote assignments
`rustfs`	S3-compatible object storage	Only for file instruments
`playground`	Instrument playground	No, and it is not started by default

Keep caddy even if you already run a reverse proxy. The web app calls the API at the relative path /api, and neither the api nor the web container publishes a port, so point your own proxy at APP_PORT instead, as in the deployment tutorial.

Profiles

Every service belongs to one or more Compose profiles. Without a profile, docker compose up -d starts every service except the playground.

Profile	Services started
(none)	caddy, api, web, mongo, rustfs, gateway
`nogateway`	caddy, api, web, mongo, rustfs
`gateway`	caddy, gateway
`fullstack`	all seven services
`playground`	playground

To use a profile without passing --profile to every command, set COMPOSE_PROFILES in .env. Docker Compose reads it from there.

Minimal stacks

Leave docker-compose.yaml unchanged, so that updating Open Data Capture with git pull never conflicts with your changes. Choose services with a profile, and put any other change in a docker-compose.override.yaml next to it, which Docker Compose merges into docker-compose.yaml automatically.

Without the gateway

Without the gateway, the instance cannot send remote assignments. Set the following in .env:

COMPOSE_PROFILES=nogateway
GATEWAY_ENABLED=false

GATEWAY_ENABLED=false turns remote assignments off in the API and hides them in the web app. Leave GATEWAY_API_KEY and GATEWAY_SITE_ADDRESS as generated, because the API still checks them when it starts.

Without file storage

Without object storage, file instruments are unavailable. Set the following in .env:

STORAGE_ENABLED=false

The other STORAGE_* variables are then ignored. Docker Compose would still start rustfs, though: it belongs to every profile that starts the api, and the api lists it as a dependency. Create docker-compose.override.yaml next to docker-compose.yaml:

services:
  api:
    depends_on: !override
      - mongo
  rustfs:
    profiles: !override
      - storage

This removes rustfs from the api’s dependencies and moves it into a storage profile that nothing activates. The !override tag requires Docker Compose 2.24.4 or later.

The smallest stack

Combine the two: the .env settings from both sections above, plus the override file. The stack then runs only caddy, api, web and mongo.

To check which services will start before launching, run:

docker compose config --services

If a service you have just left out is still running from before, stop and remove its container, for example:

docker compose rm --stop gateway