ruby/rubygems · error · Gem::RubyVersionMismatch

Your Ruby engine version is #{Gem.ruby_engine} #{RUBY_ENGINE

Error message

Your Ruby engine version is #{Gem.ruby_engine} #{RUBY_ENGINE_VERSION}, but your #{gem_deps_file} requires #{engine} #{engine_version}

What it means

Error "Your Ruby engine version is #{Gem.ruby_engine} #{RUBY_ENGINE_VERSION}, but your #{gem_deps_file} requires #{engine} #{engine_version}" thrown in ruby/rubygems.

Source

Thrown at lib/rubygems/request_set/gem_dependency_api.rb:813

                "but your #{gem_deps_file} requires #{version}"

      raise Gem::RubyVersionMismatch, message
    end

    if engine && engine != Gem.ruby_engine
      message = "Your Ruby engine is #{Gem.ruby_engine}, " \
                "but your #{gem_deps_file} requires #{engine}"

      raise Gem::RubyVersionMismatch, message
    end

    if engine_version
      if engine_version != RUBY_ENGINE_VERSION
        message =
          "Your Ruby engine version is #{Gem.ruby_engine} #{RUBY_ENGINE_VERSION}, " \
          "but your #{gem_deps_file} requires #{engine} #{engine_version}"

        raise Gem::RubyVersionMismatch, message
      end
    end

    true
  end

  ##
  # :category: Gem Dependencies DSL
  #
  # Sets +url+ as a source for gems for this dependency API.  RubyGems uses
  # the default configured sources if no source was given.  If a source is set
  # only that source is used.
  #
  # This method differs in behavior from Bundler:
  #
  # * The +:gemcutter+, # +:rubygems+ and +:rubyforge+ sources are not
  #   supported as they are deprecated in bundler.
  # * The +prepend:+ option is not supported.  If you wish to order sources

View on GitHub (pinned to 86cbb817a3)

Solutions

1. Use the engine version required by the dependencies file
2. Or update the file's engine_version requirement

When it happens

Trigger: Thrown at lib/rubygems/request_set/gem_dependency_api.rb:813 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of ruby/rubygems@86cbb817a3 (2026-08-23). Data as JSON: /api/errors/3990d3e944cc87a9. Report an issue: GitHub.