• Use Ruby 2.3+

• Edit Gemfile, by changing Hanami version: gem 'hanami', '~> 0.9'

• Edit Gemfile, by changing Hanami Model version: gem 'hanami-model', '~> 0.7'

• Edit config/environment.rb as shown below

• Edit lib/bookshelf.rb as shown below

• Edit spec/spec_helper.rb, by replacing Hanami::Application.preload! with Hanami.boot

• Edit spec/spec_helper.rb, by adding Hanami::Utils.require!("spec/support") (optional)

• Edit spec/features_helper.rb, by replacing Capybara.app = Hanami::Container.new with Capybara.app = Hanami.app

• Edit config.ru, by replacing run Hanami::Container.new with run Hanami.app

• Edit each single application configuration (eg apps/web/application.rb) by replacing digest with fingerprint in assets block(s)

• Remove custom subclasses of Hanami::Model::Coercer (if any), as PostgreSQL types are now natively supported

• Edit all the repositories (lib/bookshelf/repositories) to inherit from Hanami::Repository instead of including it

• Edit all the entities (lib/bookshelf/entities) to inherit from Hanami::Entity instead of including it

• Edit all the repositories by moving the class level methods to instance level

• Update all the repositories with the new syntax

• Edit all the entities by removing .attributes

config/environment.rb

require 'bundler/setup'
require 'hanami/setup'
require 'hanami/model' # Add this line
require_relative '../lib/bookshelf'
require_relative '../apps/web/application'
# This used to be `Hanami::Container.configure`, now it must be `Hanami.configure`
Hanami.configure do
  mount Web::Application, at: '/'
  # This is a new block
  #
  # Cut and paste the contents of `Hanami::Model.configure` from lib/bookshelf.rb
  model do
    # This used to be:
    #
    #   adapter type: :sql, url: ENV['DATABASE_URL']
    adapter :sql, ENV['DATABASE_URL']
    migrations 'db/migrations'
    schema     'db/schema.sql'
    #
    # Mapping block isn't supported anymore
    #
  end
  # This is a new block
  #
  # Cut and paste the contents of `Hanami::Mailer.configure` from lib/bookshelf.rb
  mailer do
    # Adjust the new layer `root` location
    root Hanami.root.join("lib", "bookshelf", "mailers")
    delivery do
      development :test
      test        :test
      # production :smtp, address: ENV['SMTP_PORT'], port: 1025
    end
  end
end

lib/bookshelf.rb

# This line is enough ;)
Hanami::Utils.require!("lib/bookshelf")

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