ERROR: Failed to build gem native extension.
current directory: /nix/store/yrzx9j1awsgajys5r9phy9hq6bm6f8wc-ruby2.4.0-rainbow-2.2.1/lib/ruby/gems/2.4.0/gems/rainbow-2.2.1/ext
/nix/store/6y417nc5913mdqm2dzgv5gk9ipv47myd-ruby-2.4.0/bin/ruby mkrf_conf.rb
current directory: /nix/store/yrzx9j1awsgajys5r9phy9hq6bm6f8wc-ruby2.4.0-rainbow-2.2.1/lib/ruby/gems/2.4.0/gems/rainbow-2.2.1/ext
rake RUBYARCHDIR=/nix/store/yrzx9j1awsgajys5r9phy9hq6bm6f8wc-ruby2.4.0-rainbow-2.2.1/lib/ruby/gems/2.4.0/extensions/x86_64-linux/2.4.0/rainbow-2.2.1 RUBYLIBDIR=/nix/store/yrzx9j1awsgajys5r9phy9hq6bm6f8wc-ruby2.4.0-rainbow-2.2.1/lib/ruby/gems/2.4.0/extensions/x86_64-linux/2.4.0/rainbow-2.2.1
sh: rake: command not found