Issues with High Sierra 10.13.1 and Rails?

I've tried installing Rails on a high sierra but keep receiving a "Failed to build gem native extension" error.

checking for sys/epoll.h... no

^ This is what I need to be looking at. I'm not sure if this is an issue with the new OS...possibly an issue with nio4r-2.1.0?

Building native extensions. This could take a while...
ERROR:  Error installing rails:
        ERROR: Failed to build gem native extension.

    current directory: /Users/paulkim/.rvm/gems/ruby-2.4.2/gems/nio4r-2.1.0/ext/nio4r
/Users/paulkim/.rvm/rubies/ruby-2.4.2/bin/ruby -r ./siteconf20171203-22631-czj48g.rb extconf.rb
checking for unistd.h... yes
checking for sys/select.h... yes
checking for poll.h... yes
checking for sys/epoll.h... no
checking for sys/event.h... yes
checking for sys/queue.h... yes
checking for port.h... yes
checking for sys/resource.h... yes
creating Makefile

current directory: /Users/paulkim/.rvm/gems/ruby-2.4.2/gems/nio4r-2.1.0/ext/nio4r
make "DESTDIR=" clean

current directory: /Users/paulkim/.rvm/gems/ruby-2.4.2/gems/nio4r-2.1.0/ext/nio4r
make "DESTDIR="
compiling bytebuffer.c
compiling monitor.c
compiling nio4r_ext.c
In file included from nio4r_ext.c:7:
./../libev/ev.c:488:48: warning: '/*' within block comment [-Wcomment]
/*#define MIN_INTERVAL  0.00000095367431640625 /* 1/2**20, good till 2200 */
                                               ^
./../libev/ev.c:1068:26: warning: implicit conversion loses integer precision: 'uint64_t' (aka 'unsigned long long') to 'unsigned int' [-Wshorten-64-to-32]
  return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);