"rails new" options explained

rails_new_help_output.md

Run rails new --help to view all of the options you can pass to rails new:

$ bin/rails new --help
Usage:
  rails new APP_PATH [options]

Options:
  -r, [--ruby=PATH]                                      # Path to the Ruby binary of your choice
                                                         # Default: /Users/eliot/.rbenv/versions/2.2.0/bin/ruby
  -m, [--template=TEMPLATE]                              # Path to some application template (can be a filesystem path or URL)
      [--skip-gemfile], [--no-skip-gemfile]              # Don't create a Gemfile
  -B, [--skip-bundle], [--no-skip-bundle]                # Don't run bundle install
  -G, [--skip-git], [--no-skip-git]                      # Skip .gitignore file
      [--skip-keeps], [--no-skip-keeps]                  # Skip source control .keep files
  -O, [--skip-active-record], [--no-skip-active-record]  # Skip Active Record files
  -S, [--skip-sprockets], [--no-skip-sprockets]          # Skip Sprockets files
      [--skip-spring], [--no-skip-spring]                # Don't install Spring application preloader
  -d, [--database=DATABASE]                              # Preconfigure for selected database (options: mysql/oracle/postgresql/sqlite3/frontbase/ibm_db/sqlserver/jdbcmysql/jdbcsqlite3/jdbcpostgresql/jdbc)
                                                         # Default: sqlite3
  -j, [--javascript=JAVASCRIPT]                          # Preconfigure for selected JavaScript library
                                                         # Default: jquery
  -J, [--skip-javascript], [--no-skip-javascript]        # Skip JavaScript files
      [--dev], [--no-dev]                                # Setup the application with Gemfile pointing to your Rails checkout
      [--edge], [--no-edge]                              # Setup the application with Gemfile pointing to Rails repository
      [--skip-turbolinks], [--no-skip-turbolinks]        # Skip turbolinks gem
  -T, [--skip-test-unit], [--no-skip-test-unit]          # Skip Test::Unit files
      [--rc=RC]                                          # Path to file containing extra configuration options for rails command
      [--no-rc], [--no-no-rc]                            # Skip loading of extra configuration options from .railsrc file

Runtime options:
  -f, [--force]                    # Overwrite files that already exist
  -p, [--pretend], [--no-pretend]  # Run but do not make any changes
  -q, [--quiet], [--no-quiet]      # Suppress status output
  -s, [--skip], [--no-skip]        # Skip files that already exist

Rails options:
  -h, [--help], [--no-help]        # Show this help message and quit
  -v, [--version], [--no-version]  # Show Rails version number and quit

Description:
    The 'rails new' command creates a new Rails application with a default
    directory structure and configuration at the path you specify.

    You can specify extra command-line arguments to be used every time
    'rails new' runs in the .railsrc configuration file in your home directory.

    Note that the arguments specified in the .railsrc file don't affect the
    defaults values shown above in this help message.

Example:
    rails new ~/Code/Ruby/weblog

    This generates a skeletal Rails installation in ~/Code/Ruby/weblog.
    See the README in the newly created application to get going.

Hi! How can i specify option '--database=' for mongo ?

This can help you to setup new rails application with mongodb.

keep in mind that --skip-git skip .git folder too (which created with $ git init)

Update output of rails new --help on rails 5.2.3:

Usage:
  rails new APP_PATH [options]

Options:
      [--skip-namespace], [--no-skip-namespace]            # Skip namespace (affects only isolated applications)
  -r, [--ruby=PATH]                                        # Path to the Ruby binary of your choice
                                                           # Default: /home/igor/.rvm/rubies/ruby-2.6.0/bin/ruby
  -m, [--template=TEMPLATE]                                # Path to some application template (can be a filesystem path or URL)
  -d, [--database=DATABASE]                                # Preconfigure for selected database (options: mysql/postgresql/sqlite3/oracle/frontbase/ibm_db/sqlserver/jdbcmysql/jdbcsqlite3/jdbcpostgresql/jdbc)
                                                           # Default: sqlite3
      [--skip-yarn], [--no-skip-yarn]                      # Don't use Yarn for managing JavaScript dependencies
      [--skip-gemfile], [--no-skip-gemfile]                # Don't create a Gemfile
  -G, [--skip-git], [--no-skip-git]                        # Skip .gitignore file
      [--skip-keeps], [--no-skip-keeps]                    # Skip source control .keep files
  -M, [--skip-action-mailer], [--no-skip-action-mailer]    # Skip Action Mailer files
  -O, [--skip-active-record], [--no-skip-active-record]    # Skip Active Record files
      [--skip-active-storage], [--no-skip-active-storage]  # Skip Active Storage files
  -P, [--skip-puma], [--no-skip-puma]                      # Skip Puma related files
  -C, [--skip-action-cable], [--no-skip-action-cable]      # Skip Action Cable files
  -S, [--skip-sprockets], [--no-skip-sprockets]            # Skip Sprockets files
      [--skip-spring], [--no-skip-spring]                  # Don't install Spring application preloader
      [--skip-listen], [--no-skip-listen]                  # Don't generate configuration that depends on the listen gem
      [--skip-coffee], [--no-skip-coffee]                  # Don't use CoffeeScript
  -J, [--skip-javascript], [--no-skip-javascript]          # Skip JavaScript files
      [--skip-turbolinks], [--no-skip-turbolinks]          # Skip turbolinks gem
  -T, [--skip-test], [--no-skip-test]                      # Skip test files
      [--skip-system-test], [--no-skip-system-test]        # Skip system test files
      [--skip-bootsnap], [--no-skip-bootsnap]              # Skip bootsnap gem
      [--dev], [--no-dev]                                  # Setup the application with Gemfile pointing to your Rails checkout
      [--edge], [--no-edge]                                # Setup the application with Gemfile pointing to Rails repository
      [--rc=RC]                                            # Path to file containing extra configuration options for rails command
      [--no-rc], [--no-no-rc]                              # Skip loading of extra configuration options from .railsrc file
      [--api], [--no-api]                                  # Preconfigure smaller stack for API only apps
  -B, [--skip-bundle], [--no-skip-bundle]                  # Don't run bundle install
      [--webpack=WEBPACK]                                  # Preconfigure for app-like JavaScript with Webpack (options: react/vue/angular/elm/stimulus)

Runtime options:
  -f, [--force]                    # Overwrite files that already exist
  -p, [--pretend], [--no-pretend]  # Run but do not make any changes
  -q, [--quiet], [--no-quiet]      # Suppress status output
  -s, [--skip], [--no-skip]        # Skip files that already exist

Rails options:
  -h, [--help], [--no-help]        # Show this help message and quit
  -v, [--version], [--no-version]  # Show Rails version number and quit

Description:
    The 'rails new' command creates a new Rails application with a default
    directory structure and configuration at the path you specify.

    You can specify extra command-line arguments to be used every time
    'rails new' runs in the .railsrc configuration file in your home directory.

    Note that the arguments specified in the .railsrc file don't affect the
    defaults values shown above in this help message.

Example:
    rails new ~/Code/Ruby/weblog

    This generates a skeletal Rails installation in ~/Code/Ruby/weblog.

Output for Rails 6+
https://gist.github.com/kirillshevch/1b52f711e66b064416d746f07e834c00

Hi! How can i specify option '--database=' for mongo ?

If it helps someone in future,
you can --skip-active-record and then add gem mongoid and install the gem. It generated configuration file config/mongoid.yml

From Rails 7.0.3.1

I think the one to pay special attention to because it's new and huge is: -a, [--asset-pipeline=ASSET_PIPELINE] # Choose your asset pipeline [options: sprockets (default), propshaft]

Usage:
  rails new APP_PATH [options]

Options:
      [--skip-namespace], [--no-skip-namespace]              # Skip namespace (affects only isolated engines)
      [--skip-collision-check], [--no-skip-collision-check]  # Skip collision check
  -r, [--ruby=PATH]                                          # Path to the Ruby binary of your choice
                                                             # Default: /Users/roger/.rbenv/versions/3.1.0/bin/ruby
  -m, [--template=TEMPLATE]                                  # Path to some application template (can be a filesystem path or URL)
  -d, [--database=DATABASE]                                  # Preconfigure for selected database (options: mysql/postgresql/sqlite3/oracle/sqlserver/jdbcmysql/jdbcsqlite3/jdbcpostgresql/jdbc)
                                                             # Default: sqlite3
  -G, [--skip-git], [--no-skip-git]                          # Skip .gitignore file
      [--skip-keeps], [--no-skip-keeps]                      # Skip source control .keep files
  -M, [--skip-action-mailer], [--no-skip-action-mailer]      # Skip Action Mailer files
      [--skip-action-mailbox], [--no-skip-action-mailbox]    # Skip Action Mailbox gem
      [--skip-action-text], [--no-skip-action-text]          # Skip Action Text gem
  -O, [--skip-active-record], [--no-skip-active-record]      # Skip Active Record files
      [--skip-active-job], [--no-skip-active-job]            # Skip Active Job
      [--skip-active-storage], [--no-skip-active-storage]    # Skip Active Storage files
  -C, [--skip-action-cable], [--no-skip-action-cable]        # Skip Action Cable files
  -A, [--skip-asset-pipeline], [--no-skip-asset-pipeline]    # Indicates when to generate skip asset pipeline
  -a, [--asset-pipeline=ASSET_PIPELINE]                      # Choose your asset pipeline [options: sprockets (default), propshaft]
                                                             # Default: sprockets
  -J, [--skip-javascript], [--no-skip-javascript]            # Skip JavaScript files
      [--skip-hotwire], [--no-skip-hotwire]                  # Skip Hotwire integration
      [--skip-jbuilder], [--no-skip-jbuilder]                # Skip jbuilder gem
  -T, [--skip-test], [--no-skip-test]                        # Skip test files
      [--skip-system-test], [--no-skip-system-test]          # Skip system test files
      [--skip-bootsnap], [--no-skip-bootsnap]                # Skip bootsnap gem
      [--dev], [--no-dev]                                    # Set up the application with Gemfile pointing to your Rails checkout
      [--edge], [--no-edge]                                  # Set up the application with Gemfile pointing to Rails repository
  --master, [--main], [--no-main]                            # Set up the application with Gemfile pointing to Rails repository main branch
      [--rc=RC]                                              # Path to file containing extra configuration options for rails command
      [--no-rc], [--no-no-rc]                                # Skip loading of extra configuration options from .railsrc file
      [--api], [--no-api]                                    # Preconfigure smaller stack for API only apps
      [--minimal], [--no-minimal]                            # Preconfigure a minimal rails app
  -j, [--javascript=JAVASCRIPT]                              # Choose JavaScript approach [options: importmap (default), webpack, esbuild, rollup]
                                                             # Default: importmap
  -c, [--css=CSS]                                            # Choose CSS processor [options: tailwind, bootstrap, bulma, postcss, sass... check https://github.com/rails/cssbundling-rails]
  -B, [--skip-bundle], [--no-skip-bundle]                    # Don't run bundle install

Runtime options:
  -f, [--force]                    # Overwrite files that already exist
  -p, [--pretend], [--no-pretend]  # Run but do not make any changes
  -q, [--quiet], [--no-quiet]      # Suppress status output
  -s, [--skip], [--no-skip]        # Skip files that already exist

Rails options:
  -h, [--help], [--no-help]        # Show this help message and quit
  -v, [--version], [--no-version]  # Show Rails version number and quit

Description:
    The 'rails new' command creates a new Rails application with a default
    directory structure and configuration at the path you specify.

    You can specify extra command-line arguments to be used every time
    'rails new' runs in the .railsrc configuration file in your home directory,
    or in $XDG_CONFIG_HOME/rails/railsrc if XDG_CONFIG_HOME is set.

    Note that the arguments specified in the .railsrc file don't affect the
    defaults values shown above in this help message.

Example:
    rails new ~/Code/Ruby/weblog

    This generates a skeletal Rails installation in ~/Code/Ruby/weblog.