A simple, Docker-friendly Dynamic DNS client for Cloudflare written in Go.

One of my favorite features of Google Domains was its native support for Dynamic DNS at no additional cost. Sadly, all good things come to an end. After moving all my domains to Cloudflare, I realized they didn’t offer DDNS support. Unimpressed by the alternatives, I decided to build my own.

flareDDNS is a lightweight Go application designed to run in Docker, keep your Cloudflare DNS records updated with your public IP, and provide clear, reliable logging.

• Polls your public IP address at a configurable interval.
• Creates a DNS record if one doesn’t exist.
• Updates existing records if the IP has changed.
• No-op if the DNS record already matches your current IP.
• Runs cleanly in Docker with environment-based configuration.
• Provides simple but informative logs.

• Go 1.20+ installed (Download Go)
• A Cloudflare account
• A Cloudflare API token

# Clone the repository
git clone https://github.com/nicholasarvelo/flareddns.git
cd flareddns

# Build the binary
go build -o flareddns ./cmd/flareddns

# Set required environment variables
export CF_API_TOKEN=your_cloudflare_api_token
export CF_DNS_RECORD_TYPE=A
export CF_ZONE_NAME=example.com

# Optional environment variables
export CF_DNS_RECORD=sub.example.com   # Default: null
export CF_POLLING_INTERVAL=240         # In minutes; default: 60
export CF_PROXIED=true                 # Default: false

# Run the application
./flareddns

docker run -it --rm \
  -e CF_API_TOKEN=your_cloudflare_api_token \
  -e CF_DNS_RECORD_TYPE=A \
  -e CF_ZONE_NAME=example.com \
  steptimeeditor/flareddns:latest

See LICENSE for details.