diff --git a/Rakefile b/Rakefile
index d81dd1f4..191c2fc9 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,8 +1,9 @@
-require "bundler/gem_tasks"
+require "bundler/gem_tasks" if defined?(Bundler)
 require "rake/testtask"
 
 Rake::TestTask.new(:test) do |t|
-  t.libs << "test/lib"
+  t.libs << "./test/lib"
+
   t.ruby_opts << "-rhelper"
   t.test_files = FileList["test/**/test_*.rb"]
 end
diff --git a/test/net/http/test_https.rb b/test/net/http/test_https.rb
index e9aee15b..7e6ad6ed 100644
--- a/test/net/http/test_https.rb
+++ b/test/net/http/test_https.rb
@@ -16,6 +16,7 @@ def self.read_fixture(key)
     File.read(File.expand_path("../fixtures/#{key}", __dir__))
   end
 
+  HOST = 'localhost'
   CA_CERT = OpenSSL::X509::Certificate.new(read_fixture("cacert.pem"))
   SERVER_KEY = OpenSSL::PKey.read(read_fixture("server.key"))
   SERVER_CERT = OpenSSL::X509::Certificate.new(read_fixture("server.crt"))
@@ -23,7 +24,7 @@ def self.read_fixture(key)
   TEST_STORE = OpenSSL::X509::Store.new.tap {|s| s.add_cert(CA_CERT) }
 
   CONFIG = {
-    'host' => '127.0.0.1',
+    'host' => HOST,
     'proxy_host' => nil,
     'proxy_port' => nil,
     'ssl_enable' => true,
@@ -33,7 +34,7 @@ def self.read_fixture(key)
   }
 
   def test_get
-    http = Net::HTTP.new("localhost", config("port"))
+    http = Net::HTTP.new(HOST, config("port"))
     http.use_ssl = true
     http.cert_store = TEST_STORE
     certs = []
@@ -53,7 +54,7 @@ def test_get
   end
 
   def test_get_SNI
-    http = Net::HTTP.new("localhost", config("port"))
+    http = Net::HTTP.new(HOST, config("port"))
     http.ipaddr = config('host')
     http.use_ssl = true
     http.cert_store = TEST_STORE
@@ -127,7 +128,7 @@ def test_get_SNI_failure
   end
 
   def test_post
-    http = Net::HTTP.new("localhost", config("port"))
+    http = Net::HTTP.new(HOST, config("port"))
     http.use_ssl = true
     http.cert_store = TEST_STORE
     data = config('ssl_private_key').to_der
@@ -143,7 +144,7 @@ def test_session_reuse
     # See https://github.com/openssl/openssl/pull/5967 for details.
     skip if OpenSSL::OPENSSL_LIBRARY_VERSION =~ /OpenSSL 1.1.0h/
 
-    http = Net::HTTP.new("localhost", config("port"))
+    http = Net::HTTP.new(HOST, config("port"))
     http.use_ssl = true
     http.cert_store = TEST_STORE
 
@@ -174,7 +175,7 @@ def test_session_reuse_but_expire
     # FIXME: The new_session_cb is known broken for clients in OpenSSL 1.1.0h.
     skip if OpenSSL::OPENSSL_LIBRARY_VERSION =~ /OpenSSL 1.1.0h/
 
-    http = Net::HTTP.new("localhost", config("port"))
+    http = Net::HTTP.new(HOST, config("port"))
     http.use_ssl = true
     http.cert_store = TEST_STORE
 
@@ -206,7 +207,7 @@ def test_verify
   end
 
   def test_verify_none
-    http = Net::HTTP.new("localhost", config("port"))
+    http = Net::HTTP.new(HOST, config("port"))
     http.use_ssl = true
     http.verify_mode = OpenSSL::SSL::VERIFY_NONE
     http.request_get("/") {|res|
@@ -242,7 +243,7 @@ def test_fail_if_verify_hostname_is_true
   end
 
   def test_certificate_verify_failure
-    http = Net::HTTP.new("localhost", config("port"))
+    http = Net::HTTP.new(HOST, config("port"))
     http.use_ssl = true
     ex = assert_raise(OpenSSL::SSL::SSLError){
       begin
@@ -279,10 +280,10 @@ def test_timeout_during_SSL_handshake
     bug4246 = "expected the SSL connection to have timed out but have not. [ruby-core:34203]"
 
     # listen for connections... but deliberately do not complete SSL handshake
-    TCPServer.open('localhost', 0) {|server|
+    TCPServer.open(HOST, 0) {|server|
       port = server.addr[1]
 
-      conn = Net::HTTP.new('localhost', port)
+      conn = Net::HTTP.new(HOST, port)
       conn.use_ssl = true
       conn.read_timeout = 0.01
       conn.open_timeout = 0.01
@@ -297,7 +298,7 @@ def test_timeout_during_SSL_handshake
   end
 
   def test_min_version
-    http = Net::HTTP.new("localhost", config("port"))
+    http = Net::HTTP.new(HOST, config("port"))
     http.use_ssl = true
     http.min_version = :TLS1
     http.cert_store = TEST_STORE