Environment variables from Docker, usually via --env-file .env.
DNS update rules from /home/node/app/configs/UpdaterConfig.json inside the container.

Quick Start

Pull the published image:

docker pull ghcr.io/yuzuzensai/cloudflare-ddns-updater:latest

Create .env from the example and set your Cloudflare API token:

cp .env.example .env

NODE_ENV=production
EXAMPLE_SITE_TOKEN=replace-with-cloudflare-api-token

Create configs/UpdaterConfig.json:

[
  {
    "token": "{ENV_TOKEN:EXAMPLE_SITE_TOKEN}",
    "updateInterval": 60,
    "zone": [
      {
        "id": "cloudflare-zone-id",
        "type": "A",
        "name": "example.com",
        "content": "{CURRENT_IPv4}",
        "ttl": 1,
        "proxied": false
      },
      {
        "id": "cloudflare-zone-id",
        "type": "AAAA",
        "name": "example.com",
        "content": "{CURRENT_IPv6}",
        "ttl": 1,
        "proxied": false
      }
    ]
  }
]

Run the container:

docker run -d \
  --name cloudflare-ddns-updater \
  --restart unless-stopped \
  --env-file .env \
  -v "$(pwd)/configs:/home/node/app/configs" \
  ghcr.io/yuzuzensai/cloudflare-ddns-updater:latest

View logs:

docker logs -f cloudflare-ddns-updater

Docker Compose

services:
  cloudflare-ddns-updater:
    image: ghcr.io/yuzuzensai/cloudflare-ddns-updater:latest
    container_name: cloudflare-ddns-updater
    restart: unless-stopped
    env_file:
      - .env
    volumes:
      - ./configs:/home/node/app/configs

docker compose up -d

Configuration

configs/UpdaterConfig.json is an array of Cloudflare account/token configurations.

Each top-level object:

Field	Description
`token`	Cloudflare API token, or an environment reference like `{ENV_TOKEN:EXAMPLE_SITE_TOKEN}`
`updateInterval`	Update interval in seconds
`zone`	DNS records to manage

Each zone entry:

Field	Description
`id`	Cloudflare zone ID
`type`	DNS record type, usually `A` or `AAAA`
`name`	DNS record name, e.g. `example.com` or `home.example.com`
`content`	`{CURRENT_IPv4}` for an `A` record, `{CURRENT_IPv6}` for an `AAAA` record
`ttl`	Cloudflare TTL. Use `1` for automatic
`proxied`	Cloudflare proxy status, `true` or `false`

Cloudflare Zone ID and API Token

Zone ID — In the Cloudflare dashboard, select the domain, open its overview page, and copy Zone ID from the API section of the right sidebar into zone[].id.

API token — In the dashboard, go to your profile icon → My Profile → API Tokens → Create Token. Use the built-in Edit zone DNS template (recommended) or a custom token with Zone > DNS > Edit and Zone > Zone > Read permissions. Either way, scope Zone Resources to Include → Specific zone → your domain, then create and copy the token — Cloudflare only shows it once. Don't use your Global API Key; the updater only needs a scoped token for the zones it manages.

Put the token in .env under any variable name you like, then reference that same name from UpdaterConfig.json:

HOME_SITE_TOKEN=your-cloudflare-api-token

"token": "{ENV_TOKEN:HOME_SITE_TOKEN}"

Avoid writing the literal token directly into UpdaterConfig.json — {ENV_TOKEN:...} keeps the secret in .env, which is gitignored.

Development

bun install
bun run dev     # run with --watch
bun run check   # typecheck + format + lint + test

Notes

IPv4 is looked up via https://api.ipify.org?format=json, IPv6 via https://api64.ipify.org/?format=json.
If configs/UpdaterConfig.json is missing, the app creates one from the bundled example — edit it before real use.