RailsCaddyDev

Automatically configures Caddy as a local reverse proxy for Rails development. When you start rails server, it registers routes via the Caddy admin API so that <project_name>.localhost proxies to your locally running Rails server with HTTPS.

• Caddy installed and running locally
• Ruby >= 3.1

Add it to your application's Gemfile:

gem 'rails_caddy_dev', group: :development

Then run:

bundle install

In your application's bin/rails file, replace this:

require "rails/commands"

with this:

require ENV.key?('DEVCADDY') ? "rails_caddy_dev/commands" : "rails/commands"

This will ensure your Caddy configuration is updated each time you start your Rails server in development.

Start your Rails server with the DEVCADDY and PROJECT_NAME environment variables:

DEVCADDY=1 PROJECT_NAME=myapp rails server

This will configure Caddy to proxy myapp.localhost to your Rails server, accessible over HTTPS.

If PORT is not set, the gem automatically detects an available TCP port and uses it. This means you can run multiple Rails servers without port conflicts — no manual configuration needed.

You can also use the standalone executable to find an available port yourself:

export PORT=$(bundle exec rails_caddy_dev port)

Subdomains are also supported due to a wildcard Caddy route that will be configured. For example, if you set PROJECT_NAME=myapp, then api.myapp.localhost will also proxy to your Rails server.

After checking out the repo, run bin/setup to install dependencies. Then, run bundle exec rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

Bug reports and pull requests are welcome on GitHub at https://github.com/joelmoss/rails_caddy_dev.

The gem is available as open source under the terms of the MIT License.