ngrok is a great tool for exposing local services to the world with the magic of reverse proxies:

Spend more time programming. One command for an instant, secure URL to your localhost server through any NAT or firewall.

However, using ngrok with a custom domain is a paid feature, and there are usage limits on the free tier.

Enter bifrost!

The repo provides terraform scripts for setting up a free f1-micro instance on Google Cloud Platform, as well as Ansible to set up the required nginx configuration.

Once configured, the server acts as a personal ngrok clone with a custom domain.

Simply running ./bifrost http hello 127.0.0.1:3000 exposes a local webserver running on port 3000 to the world at hello.bifrost.kylesferrazza.com with the default domain configuration.

The terraform scripts even provision a wildcard TLS certificate for the bifrost subdomain, allowing nginx to serve valid TLS configurations for all of the proxied sites.