diff --git a/lib/psych.rb b/lib/psych.rb
index ecf3b392..38307878 100644
--- a/lib/psych.rb
+++ b/lib/psych.rb
@@ -1,8 +1,8 @@
 # frozen_string_literal: true
-require 'psych/versions'
+require_relative 'psych/versions'
 case RUBY_ENGINE
 when 'jruby'
-  require 'psych_jars'
+  require_relative 'psych_jars'
   if JRuby::Util.respond_to?(:load_ext)
     JRuby::Util.load_ext('org.jruby.ext.psych.PsychLibrary')
   else
@@ -12,21 +12,21 @@
 else
   require 'psych.so'
 end
-require 'psych/nodes'
-require 'psych/streaming'
-require 'psych/visitors'
-require 'psych/handler'
-require 'psych/tree_builder'
-require 'psych/parser'
-require 'psych/omap'
-require 'psych/set'
-require 'psych/coder'
-require 'psych/core_ext'
-require 'psych/stream'
-require 'psych/json/tree_builder'
-require 'psych/json/stream'
-require 'psych/handlers/document_stream'
-require 'psych/class_loader'
+require_relative 'psych/nodes'
+require_relative 'psych/streaming'
+require_relative 'psych/visitors'
+require_relative 'psych/handler'
+require_relative 'psych/tree_builder'
+require_relative 'psych/parser'
+require_relative 'psych/omap'
+require_relative 'psych/set'
+require_relative 'psych/coder'
+require_relative 'psych/core_ext'
+require_relative 'psych/stream'
+require_relative 'psych/json/tree_builder'
+require_relative 'psych/json/stream'
+require_relative 'psych/handlers/document_stream'
+require_relative 'psych/class_loader'
 
 ###
 # = Overview
diff --git a/lib/psych/class_loader.rb b/lib/psych/class_loader.rb
index 088373cd..c2e4ea4c 100644
--- a/lib/psych/class_loader.rb
+++ b/lib/psych/class_loader.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
-require 'psych/omap'
-require 'psych/set'
+require_relative 'omap'
+require_relative 'set'
 
 module Psych
   class ClassLoader # :nodoc:
diff --git a/lib/psych/core_ext.rb b/lib/psych/core_ext.rb
index 81055cc5..0721a133 100644
--- a/lib/psych/core_ext.rb
+++ b/lib/psych/core_ext.rb
@@ -15,5 +15,5 @@ def to_yaml options = {}
 end
 
 if defined?(::IRB)
-  require 'psych/y'
+  require_relative 'y'
 end
diff --git a/lib/psych/handlers/document_stream.rb b/lib/psych/handlers/document_stream.rb
index 67da7940..b77115d0 100644
--- a/lib/psych/handlers/document_stream.rb
+++ b/lib/psych/handlers/document_stream.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'psych/tree_builder'
+require_relative '../tree_builder'
 
 module Psych
   module Handlers
diff --git a/lib/psych/handlers/recorder.rb b/lib/psych/handlers/recorder.rb
index a8fc7b11..c98724cb 100644
--- a/lib/psych/handlers/recorder.rb
+++ b/lib/psych/handlers/recorder.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'psych/handler'
+require_relative '../handler'
 
 module Psych
   module Handlers
diff --git a/lib/psych/json/stream.rb b/lib/psych/json/stream.rb
index 2ebd3d7a..24dd4b9b 100644
--- a/lib/psych/json/stream.rb
+++ b/lib/psych/json/stream.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
-require 'psych/json/ruby_events'
-require 'psych/json/yaml_events'
+require_relative 'ruby_events'
+require_relative 'yaml_events'
 
 module Psych
   module JSON
diff --git a/lib/psych/json/tree_builder.rb b/lib/psych/json/tree_builder.rb
index 5c2ee8ca..9a45f6b9 100644
--- a/lib/psych/json/tree_builder.rb
+++ b/lib/psych/json/tree_builder.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'psych/json/yaml_events'
+require_relative 'yaml_events'
 
 module Psych
   module JSON
diff --git a/lib/psych/nodes.rb b/lib/psych/nodes.rb
index 5842c2e3..2fa52e00 100644
--- a/lib/psych/nodes.rb
+++ b/lib/psych/nodes.rb
@@ -1,11 +1,11 @@
 # frozen_string_literal: true
-require 'psych/nodes/node'
-require 'psych/nodes/stream'
-require 'psych/nodes/document'
-require 'psych/nodes/sequence'
-require 'psych/nodes/scalar'
-require 'psych/nodes/mapping'
-require 'psych/nodes/alias'
+require_relative 'nodes/node'
+require_relative 'nodes/stream'
+require_relative 'nodes/document'
+require_relative 'nodes/sequence'
+require_relative 'nodes/scalar'
+require_relative 'nodes/mapping'
+require_relative 'nodes/alias'
 
 module Psych
   ###
diff --git a/lib/psych/nodes/node.rb b/lib/psych/nodes/node.rb
index 05cb08da..1f841625 100644
--- a/lib/psych/nodes/node.rb
+++ b/lib/psych/nodes/node.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 require 'stringio'
-require 'psych/class_loader'
-require 'psych/scalar_scanner'
+require_relative '../class_loader'
+require_relative '../scalar_scanner'
 
 module Psych
   module Nodes
diff --git a/lib/psych/syntax_error.rb b/lib/psych/syntax_error.rb
index 1598e6ff..a4c9c4a3 100644
--- a/lib/psych/syntax_error.rb
+++ b/lib/psych/syntax_error.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'psych/exception'
+require_relative 'exception'
 
 module Psych
   class SyntaxError < Psych::Exception
diff --git a/lib/psych/tree_builder.rb b/lib/psych/tree_builder.rb
index 47a16956..414ca02b 100644
--- a/lib/psych/tree_builder.rb
+++ b/lib/psych/tree_builder.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'psych/handler'
+require_relative 'handler'
 
 module Psych
   ###
diff --git a/lib/psych/visitors.rb b/lib/psych/visitors.rb
index e2b084da..508290d8 100644
--- a/lib/psych/visitors.rb
+++ b/lib/psych/visitors.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
-require 'psych/visitors/visitor'
-require 'psych/visitors/to_ruby'
-require 'psych/visitors/emitter'
-require 'psych/visitors/yaml_tree'
-require 'psych/visitors/json_tree'
-require 'psych/visitors/depth_first'
+require_relative 'visitors/visitor'
+require_relative 'visitors/to_ruby'
+require_relative 'visitors/emitter'
+require_relative 'visitors/yaml_tree'
+require_relative 'visitors/json_tree'
+require_relative 'visitors/depth_first'
diff --git a/lib/psych/visitors/json_tree.rb b/lib/psych/visitors/json_tree.rb
index 9912cb13..979fc100 100644
--- a/lib/psych/visitors/json_tree.rb
+++ b/lib/psych/visitors/json_tree.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'psych/json/ruby_events'
+require_relative '../json/ruby_events'
 
 module Psych
   module Visitors
diff --git a/lib/psych/visitors/to_ruby.rb b/lib/psych/visitors/to_ruby.rb
index 4de7f80d..4c1f5610 100644
--- a/lib/psych/visitors/to_ruby.rb
+++ b/lib/psych/visitors/to_ruby.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
-require 'psych/scalar_scanner'
-require 'psych/class_loader'
-require 'psych/exception'
+require_relative '../scalar_scanner'
+require_relative '../class_loader'
+require_relative '../exception'
 
 unless defined?(Regexp::NOENCODING)
   Regexp::NOENCODING = 32
diff --git a/lib/psych/visitors/yaml_tree.rb b/lib/psych/visitors/yaml_tree.rb
index 2eee4d34..316a3a94 100644
--- a/lib/psych/visitors/yaml_tree.rb
+++ b/lib/psych/visitors/yaml_tree.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
-require 'psych/tree_builder'
-require 'psych/scalar_scanner'
-require 'psych/class_loader'
+require_relative '../tree_builder'
+require_relative '../scalar_scanner'
+require_relative '../class_loader'
 
 module Psych
   module Visitors