diff --git a/.gitignore b/.gitignore
index c1ecbde..e111274 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,6 +9,7 @@ InstalledFiles
 _yardoc
 coverage
 doc/
+generated-source/
 lib/bundler/man
 pkg
 rdoc
diff --git a/Rakefile b/Rakefile
index 2995527..f6534e1 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1 +1,345 @@
-require "bundler/gem_tasks"
+# frozen_string_literal: true
+
+GENERATED_SOURCE_DIR = 'generated-source'
+GENERATED_NAMESPACE = :HiveMetastore
+HIVE_METASTORE_NAMESPACE = :HiveMetastore
+SERDE_NAMESPACE = :Serde
+
+require 'rake/clean'
+CLOBBER.include 'pkg'
+
+EXCLUSIONS = [
+  '.git', '.gitignore',
+  'Gemfile', 'Gemfile.lock',
+  'pkg',
+  GENERATED_SOURCE_DIR
+].freeze
+
+require 'rubygems/specification'
+GEMSPEC = Gem::Specification.load(File.join(__dir__, 'rbhive.gemspec'))
+
+require 'pathname'
+def copy_source_files
+  entries = Pathname.new(__dir__).children
+  Dir.mkdir File.join(__dir__, GENERATED_SOURCE_DIR)
+  entries.each do |f|
+    unless EXCLUSIONS.include?(f.basename.to_s)
+      FileUtils.cp_r f, File.join(GENERATED_SOURCE_DIR, f.basename)
+    end
+  end
+end
+
+module PlainName
+
+  private
+
+  def plain_name(node)
+    if node.nil?
+      [nil]
+    elsif node.is_a? Symbol
+      [node]
+    elsif node.is_a? Parser::AST::Node
+      case node.type
+      when :const, :casgn
+        plain_name(node.children[0]) + plain_name(node.children[1])
+      when :cbase
+        [:'::']
+      else
+        raise ArgumentError, "Unexpected node type: #{node.type}"
+      end
+    else
+      raise ArgumentError, "Unexpected node class: #{node.class}"
+    end
+  end
+
+  def plain_namespace(node)
+    name = plain_name(node)
+    if name.first.nil?
+      (namespace || [:'::']) + name[1..-1]
+    else
+      name
+    end
+  end
+end
+
+require 'parser/current'
+class NameTracker < Parser::AST::Processor
+  include PlainName
+
+  def initialize
+    super
+    @names = {}
+    @namespace_stack = [[:'::']]
+  end
+
+  attr_reader :names
+
+  def on_module(node)
+    name, body = *node
+    remember_name(name)
+    namespace_stack.push plain_namespace(name)
+    process(body)
+    namespace_stack.pop
+    node
+  end
+
+  def on_class(node)
+    name, superclass, body = *node
+    remember_name(name)
+    remember_name(superclass) if superclass
+    namespace_stack.push plain_namespace(name)
+    process(body)
+    namespace_stack.pop
+    node
+  end
+
+  def on_casgn(node)
+    remember_name(node)
+    super node
+  end
+
+  private
+
+  attr_reader :namespace_stack
+
+  def namespace
+    namespace_stack.last
+  end
+
+  def remember_name(node)
+    plain_name = plain_name(node)
+    plain_name =
+      if plain_name.first.nil?
+        namespace + plain_name[1..-1]
+      else
+        plain_name
+      end
+    plain_name.reduce(names) do |names, name|
+      names[name] ||= {}
+    end
+  end
+end
+
+class RenamedConstDetector < Parser::AST::Processor
+  include PlainName
+
+  def initialize(names)
+    @names = names
+    @namespace_stack = [[:'::']]
+    @renamed_consts = []
+  end
+
+  attr_reader :renamed_consts
+
+  def on_module(node)
+    name = node.children[0]
+    namespace_stack.push plain_namespace(name)
+    new_node = super(node)
+    namespace_stack.pop
+    new_node
+  end
+
+  def on_class(node)
+    name = node.children[0]
+    namespace_stack.push plain_namespace(name)
+    new_node = super(node)
+    namespace_stack.pop
+    new_node
+  end
+
+  def on_const(node)
+    new_namespace = namespace_for(node)
+    if new_namespace
+      renamed_consts << [node, new_namespace]
+    else
+      node
+    end
+  end
+
+  private
+
+  attr_reader :namespace_stack, :names
+
+  def namespace
+    namespace_stack.last
+  end
+
+  def namespace_for(node)
+    name = plain_name(node)
+
+    [
+      HIVE_METASTORE_NAMESPACE,
+      SERDE_NAMESPACE
+    ].each do |generated_namespace|
+      if name.first.nil?
+        # Relative name
+        namespace_stack.reverse_each do |namespace|
+          renamed_name = [
+            namespace[0],
+            generated_namespace,
+            *namespace[1..-1],
+            *name[1..-1]
+          ]
+          found = renamed_name.reduce(names) do |names, segment|
+            names ? names[segment] : names
+          end
+          return generated_namespace if found
+        end
+      elsif name.first == :'::'
+        # Absolute name
+        renamed_name = [
+          name[0],
+          generated_namespace,
+          *name[1..-1]
+        ]
+        found = renamed_name.reduce(names) do |names, segment|
+          names ? names[segment] : names
+        end
+        return generated_namespace if found
+      end
+    end
+    nil
+  end
+end
+
+def deep_merge_names(hash1, hash2)
+  hash1.merge(hash2) do |_key, val1, val2|
+    if val1.is_a?(Hash) && val2.is_a?(Hash)
+      deep_merge_names(val1, val2)
+    else
+      val2
+    end
+  end
+end
+
+def namespace_file(filename, namespace)
+  parser = Parser::CurrentRuby.new
+  parser.builder.emit_file_line_as_literals = false
+
+  source = File.read(filename).force_encoding(parser.default_encoding)
+
+  source = "module #{namespace}\n#{source}\nend"
+  File.write(filename, source)
+
+  buffer = Parser::Source::Buffer.new(filename)
+  buffer.source = source
+  ast = parser.parse(buffer)
+
+  name_tracker = NameTracker.new
+  name_tracker.process(ast)
+
+  name_tracker.names
+end
+
+def fix_thrift
+  parser = Parser::CurrentRuby.new
+  parser.builder.emit_file_line_as_literals = false
+  names = {}
+
+  Dir[File.join(__dir__, GENERATED_SOURCE_DIR, 'lib', 'thrift',
+                'hive_metastore_{constants,types}.rb')]
+    .each do |filename|
+    names = deep_merge_names(
+      names,
+      namespace_file(filename, HIVE_METASTORE_NAMESPACE)
+    )
+  end
+
+  Dir[File.join(__dir__, GENERATED_SOURCE_DIR, 'lib', 'thrift',
+                'serde_{constants,types}.rb')]
+    .each do |filename|
+    names = deep_merge_names(
+      names,
+      namespace_file(filename, SERDE_NAMESPACE)
+    )
+  end
+
+  names
+end
+
+def namespace_constants(filename, names, options = {})
+  parser = Parser::CurrentRuby.new
+  parser.builder.emit_file_line_as_literals = false
+  parser.builder.class.emit_index = true
+
+  source = File.read(filename).force_encoding(parser.default_encoding)
+  buffer = Parser::Source::Buffer.new(filename)
+  buffer.source = source
+
+  ast = parser.parse(buffer)
+  renamed_const_detector = RenamedConstDetector.new(names)
+  renamed_const_detector.process(ast)
+
+  renamed_const_detector
+    .renamed_consts
+    .sort_by { |node, _ns| node.location.expression.begin_pos }
+    .reverse_each do |node, generated_namespace|
+    range = Range.new(
+      node.location.expression.begin_pos,
+      node.location.expression.end_pos,
+      true
+    )
+    const = source[range]
+    new_const =
+      if const[0, 2] == '::'
+        "::#{generated_namespace}#{const}"
+      else
+        next if options[:absolute_only]
+        "#{generated_namespace}::#{const}"
+      end
+    source[range] = new_const
+  end
+  File.write(filename, source)
+end
+
+def fix_rbhive(names)
+  Dir[File.join(__dir__, GENERATED_SOURCE_DIR, 'lib', 'rbhive', '*.rb')]
+    .each do |filename|
+    namespace_constants(filename, names)
+  end
+
+  Dir[File.join(__dir__, GENERATED_SOURCE_DIR, 'lib', 'thrift', '*.rb')]
+    .each do |filename|
+    namespace_constants(filename, names, absolute_only: true)
+  end
+end
+
+def prepare_source
+  clean_up_generated_source
+  copy_source_files
+  new_names = fix_thrift
+  fix_rbhive(new_names)
+end
+
+def clean_up_generated_source
+  FileUtils.rm_r(GENERATED_SOURCE_DIR) if File.exist?(GENERATED_SOURCE_DIR)
+end
+
+def keep_gem
+  built_gem_path =
+    Dir[File.join(GENERATED_SOURCE_DIR, "#{GEMSPEC.name}-*.gem")]
+    .max_by { |f| File.mtime(f) }
+
+  file_name = File.basename(built_gem_path)
+  FileUtils.mkdir_p('pkg')
+  FileUtils.mv(built_gem_path, 'pkg')
+  puts "#{GEMSPEC.name} #{GEMSPEC.version} built to pkg/#{file_name}"
+end
+
+def with_generated_source
+  prepare_source
+  Dir.chdir(GENERATED_SOURCE_DIR) do
+    yield
+  end
+  keep_gem
+ensure
+  clean_up_generated_source unless ENV['PRESERVE_GENERATED']
+end
+
+desc "Build #{GEMSPEC.name}-#{GEMSPEC.version}.gem into the pkg directory."
+task :build do
+  with_generated_source do
+    gem = ENV['BUNDLE_GEM'] || 'gem'
+    system "#{gem} build -V #{GEMSPEC.name}.gemspec"
+  end
+end
diff --git a/lib/rbhive/t_c_l_i_connection.rb b/lib/rbhive/t_c_l_i_connection.rb
index e1839e9..5683cec 100644
--- a/lib/rbhive/t_c_l_i_connection.rb
+++ b/lib/rbhive/t_c_l_i_connection.rb
@@ -394,7 +394,7 @@ def prepare_fetch_results(handle, orientation=:first, rows=100)
       unless valid_orientations.include?(orientation_value)
         raise ArgumentError, "Invalid orientation: #{orientation.inspect}"
       end
-      orientation_const = eval("::Hive2::Thrift::TFetchOrientation::#{orientation_value}")
+      orientation_const = ::Hive2::Thrift::TFetchOrientation.const_get(orientation_value)
       ::Hive2::Thrift::TFetchResultsReq.new(
         operationHandle: handle,
         orientation: orientation_const,
diff --git a/rbhive.gemspec b/rbhive.gemspec
index d2b6601..1a0c3b6 100644
--- a/rbhive.gemspec
+++ b/rbhive.gemspec
@@ -13,7 +13,7 @@ Gem::Specification.new do |spec|
   spec.homepage = 'http://github.com/forward3d/rbhive'
   spec.license = 'MIT'
 
-  spec.files = `git ls-files`.split($/)
+  spec.files = Dir[File.join(__dir__, '**', '*')]
   spec.executables   = spec.files.grep(%r{^bin/}) { |f| File.basename(f) }
   spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
   spec.require_paths = ['lib']
@@ -23,5 +23,5 @@ Gem::Specification.new do |spec|
 
   spec.add_development_dependency 'rake'
   spec.add_development_dependency 'bundler', '>= 1.3'
-
+  spec.add_development_dependency 'parser', '>= 2.6.3.0'
 end