FEATURE: add support for bootsnap in dev

To use bootsnap which speeds up rails boot add

BOOTSNAP=1 to your env

Gemfile

@@ -1,6 +1,7 @@
 source 'https://rubygems.org'
 # if there is a super emergency and rubygems is playing up, try
 #source 'http://production.cf.rubygems.org'
+gem 'bootsnap', require: false
 
 def rails_master?
   ENV["RAILS_MASTER"] == '1'

Gemfile.lock

@@ -62,6 +62,9 @@ GEM
       rack (>= 0.9.0)
     binding_of_caller (0.7.2)
       debug_inspector (>= 0.0.1)
+    bootsnap (0.2.10)
+      msgpack (~> 1.0)
+      snappy (~> 0.0.15)
     builder (3.2.3)
     bullet (5.4.2)
       activesupport (>= 3.0.0)
@@ -166,7 +169,7 @@ GEM
       metaclass (~> 0.0.1)
     mock_redis (0.15.4)
     moneta (1.0.0)
-    msgpack (1.0.2)
+    msgpack (1.1.0)
     multi_json (1.12.1)
     multi_xml (0.6.0)
     multipart-post (2.0.0)
@@ -354,6 +357,7 @@ GEM
       rack-protection (~> 1.4)
       tilt (>= 1.3, < 3)
     slop (3.6.0)
+    snappy (0.0.15)
     spork (1.0.0rc4)
     spork-rails (4.0.0)
       rails (>= 3.0.0, < 5)
@@ -400,6 +404,7 @@ DEPENDENCIES
   barber
   better_errors
   binding_of_caller
+  bootsnap
   bullet
   byebug
   certified

config/boot.rb

@@ -9,3 +9,16 @@ require 'rubygems'
 ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../Gemfile', __FILE__)
 
 require 'bundler/setup' if File.exists?(ENV['BUNDLE_GEMFILE'])
+
+if ENV['BOOTSNAP'] #&& ENV['RAILS_ENV'] != 'production'
+  require 'bootsnap'
+  Bootsnap.setup(
+    cache_dir:            'tmp/cache', # Path to your cache
+    development_mode:     ENV['BOOTSNAP_DEV'] == 'development',
+    load_path_cache:      true,        # Should we optimize the LOAD_PATH with a cache?
+    autoload_paths_cache: true,        # Should we optimize ActiveSupport autoloads with cache?
+    disable_trace:        false,       # Sets `RubyVM::InstructionSequence.compile_option = { trace_instruction: false }`
+    compile_cache_iseq:   true,        # Should compile Ruby code into ISeq cache?
+    compile_cache_yaml:   true         # Should compile YAML into a cache?
+  )
+end