diff --git a/.gitignore b/.gitignore
index 21dc82a5..e915bb22 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+.idea/
 jwt.gemspec
 pkg
 Gemfile.lock
diff --git a/.travis.yml b/.travis.yml
index b5097ba8..a65dad05 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,6 +2,7 @@ sudo: false
 cache: bundler
 language: ruby
 rvm:
+  - 1.9.3
   - 2.0.0
   - 2.1.0
   - 2.2.0
diff --git a/lib/jwt/verify.rb b/lib/jwt/verify.rb
index 23bfb7f3..7634fd07 100644
--- a/lib/jwt/verify.rb
+++ b/lib/jwt/verify.rb
@@ -4,7 +4,7 @@ module JWT
   # JWT verify methods
   class Verify
     class << self
-      %i[verify_aud verify_expiration verify_iat verify_iss verify_jti verify_not_before verify_sub].each do |method_name|
+      %w[verify_aud verify_expiration verify_iat verify_iss verify_jti verify_not_before verify_sub].each do |method_name|
         define_method method_name do |payload, options|
           new(payload, options).send(method_name)
         end
@@ -17,7 +17,7 @@ def initialize(payload, options)
     end
 
     def verify_aud
-      return unless options_aud = extract_option(:aud)
+      return unless (options_aud = extract_option(:aud))
 
       if @payload['aud'].is_a?(Array)
         fail(
@@ -49,7 +49,7 @@ def verify_iat
     end
 
     def verify_iss
-      return unless options_iss = extract_option(:iss)
+      return unless (options_iss = extract_option(:iss))
 
       if @payload['iss'].to_s != options_iss.to_s
         fail(
@@ -77,7 +77,7 @@ def verify_not_before
     end
 
     def verify_sub
-      return unless options_sub = extract_option(:sub)
+      return unless (options_sub = extract_option(:sub))
 
       fail(
         JWT::InvalidSubError,
diff --git a/ruby-jwt.gemspec b/ruby-jwt.gemspec
index b93176ca..031a10a0 100644
--- a/ruby-jwt.gemspec
+++ b/ruby-jwt.gemspec
@@ -26,5 +26,4 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'simplecov'
   spec.add_development_dependency 'simplecov-json'
   spec.add_development_dependency 'codeclimate-test-reporter'
-  spec.add_development_dependency 'byebug'
 end