rom-repo-starter.rb

require 'bundler/inline'

gemfile(true) do
  source 'https://rubygems.org'
  gem 'rom', github: 'rom-rb/rom'
  gem 'rom-sql', github: 'rom-rb/rom-sql'
  gem 'rom-repository', github: 'rom-rb/rom-repository'
  gem 'sqlite3'
end

config = ROM::Configuration.new(:sql, 'sqlite::memory')

gateway = config.gateways[:default]
migrations = []

migrations << gateway.migration do
  change do
    create_table :users do
      primary_key :id
      column :name, String, null: false
    end
  end
end

migrations.each do |migration|
  migration.apply(gateway.connection, :up)
end

class Users < ROM::Relation[:sql]
  def by_id(id)
    where(id: id)
  end
end

config.register_relation(Users)

rom = ROM.container(config)

class UserRepo < ROM::Repository[:users]
  commands :create, update: :by_id, delete: :by_id

  def [](id)
    users.by_id(id).one
  end
end

repo = UserRepo.new(rom)

user = repo.create(name: 'Jane')