bundle install не может найти версию ruby

Получаю ошибку при выполнении команды bundle install, помогите разобраться:

Fetching gem metadata from https://rubygems.org/...........
Fetching gem metadata from https://rubygems.org/.
Resolving dependencies.....
Bundler could not find compatible versions for gem "ruby ":
In Gemfile:
  ruby

metasploit-framework was resolved to 5.0.95, which depends on
  msgpack was resolved to 1.3.3, which depends on
    ruby  (< 2.8.dev, >= 2.2) x86-mingw32

metasploit-framework was resolved to 5.0.95, which depends on
  nokogiri was resolved to 1.10.9, which depends on
    ruby  (< 2.7.dev, >= 2.3) x86-mingw32

metasploit-framework was resolved to 5.0.95, which depends on
  pg (~> 0.20) was resolved to 0.21.0, which depends on
    ruby  (< 2.5, >= 2.0) x86-mingw32

sqlite3 (~> 1.3.0) was resolved to 1.3.13, which depends on
  ruby  (>= 1.8.7) x86-mingw32

Could not find gem 'ruby  (< 2.5, >= 2.0)', which is required by gem 'sqlite3
(~> 1.3.0)', in any of the relevant sources:
  the local ruby installation