diff --git a/rbvmomi.gemspec b/rbvmomi.gemspec
index 0056cc2b..cb4e324f 100644
--- a/rbvmomi.gemspec
+++ b/rbvmomi.gemspec
@@ -1,7 +1,7 @@
-# Copyright (c) 2016-2017 VMware, Inc.  All Rights Reserved.
+# Copyright (c) 2016-2020 VMware, Inc.  All Rights Reserved.
 # SPDX-License-Identifier: MIT
 
-$LOAD_PATH.unshift(File.expand_path('../lib', __FILE__))
+$LOAD_PATH.unshift(File.expand_path('lib', __dir__))
 
 require 'rbvmomi/version'
 
@@ -16,18 +16,19 @@ Gem::Specification.new do |spec|
   spec.license  = 'MIT'
 
   spec.bindir = 'exe'
-  spec.files  = %w{LICENSE README.md vmodl.db} + Dir.glob("{lib,exe}/**/*")
+  spec.files  = %w[LICENSE README.md vmodl.db] + Dir.glob('{lib,exe}/**/*')
   spec.executables << 'rbvmomish'
 
-  spec.add_runtime_dependency('builder', '~> 3.0')
-  spec.add_runtime_dependency('json', '>= 1.8')
-  spec.add_runtime_dependency('nokogiri', '~> 1.5')
+  spec.add_runtime_dependency('builder', '~> 3.2')
+  spec.add_runtime_dependency('json', '~> 2.3')
+  spec.add_runtime_dependency('nokogiri', '~> 1.10')
   spec.add_runtime_dependency('optimist', '~> 3.0')
 
-  spec.add_development_dependency('rake', '~> 10.5')
-  spec.add_development_dependency('simplecov', '~> 0.12.0')
-  spec.add_development_dependency('yard', '~> 0.9.5')
-  spec.add_development_dependency('test-unit', '>= 2.5')
+  spec.add_development_dependency('pry', '~> 0.13.1')
+  spec.add_development_dependency('rake', '~> 13.0')
+  spec.add_development_dependency('simplecov', '~> 0.18.5')
+  spec.add_development_dependency('yard', '~> 0.9.25')
+  spec.add_development_dependency('test-unit', '~> 3.3')
 
   spec.required_ruby_version = '>= 2.4.1'
 end