diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 376bb8d..872e0e0 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,10 +17,10 @@ jobs:
     steps:
       - uses: actions/checkout@v3
 
-      - name: Set up Ruby 2.7
+      - name: Set up Ruby 3.x
         uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 2.7
+          ruby-version: 3
           bundler-cache: true
 
       - name: Rubocop
@@ -31,7 +31,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby: ['2.6', '2.7', '3.0', '3.1', '3.2']
+        ruby: ['2.7', '3.0', '3.1', '3.2', '3.3']
 
     steps:
       - uses: actions/checkout@v3
diff --git a/.gitignore b/.gitignore
index 8db0476..2e08a92 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,7 +10,7 @@ spec/reports/
 tmp/
 
 *.gem
-gemfile.lock
+Gemfile.lock
 
 .rvmrc
 .ruby-version
diff --git a/.rubocop.yml b/.rubocop.yml
index f300a1e..c361dc1 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -7,7 +7,7 @@ require:
 AllCops:
   DisplayCopNames: true
   DisplayStyleGuide: true
-  TargetRubyVersion: 2.4
+  TargetRubyVersion: 2.6
 
 Metrics/BlockLength:
   Exclude:
@@ -56,3 +56,242 @@ Style/IfUnlessModifier:
 Style/SlicingWithRange: # (0.83)
   Enabled: true
 
+# New Cops
+Gemspec/DeprecatedAttributeAssignment: # new in 1.30
+  Enabled: true
+Gemspec/DevelopmentDependencies: # new in 1.44
+  Enabled: true
+Gemspec/RequireMFA: # new in 1.23
+  Enabled: true
+Layout/LineContinuationLeadingSpace: # new in 1.31
+  Enabled: true
+Layout/LineContinuationSpacing: # new in 1.31
+  Enabled: true
+Layout/LineEndStringConcatenationIndentation: # new in 1.18
+  Enabled: true
+Layout/SpaceBeforeBrackets: # new in 1.7
+  Enabled: true
+Lint/AmbiguousAssignment: # new in 1.7
+  Enabled: true
+Lint/AmbiguousOperatorPrecedence: # new in 1.21
+  Enabled: true
+Lint/AmbiguousRange: # new in 1.19
+  Enabled: true
+Lint/ConstantOverwrittenInRescue: # new in 1.31
+  Enabled: true
+Lint/DeprecatedConstants: # new in 1.8
+  Enabled: true
+Lint/DuplicateBranch: # new in 1.3
+  Enabled: true
+Lint/DuplicateMagicComment: # new in 1.37
+  Enabled: true
+Lint/DuplicateMatchPattern: # new in 1.50
+  Enabled: true
+Lint/DuplicateRegexpCharacterClassElement: # new in 1.1
+  Enabled: true
+Lint/EmptyBlock: # new in 1.1
+  Enabled: true
+Lint/EmptyClass: # new in 1.3
+  Enabled: true
+Lint/EmptyInPattern: # new in 1.16
+  Enabled: true
+Lint/IncompatibleIoSelectWithFiberScheduler: # new in 1.21
+  Enabled: true
+Lint/ItWithoutArgumentsInBlock: # new in 1.59
+  Enabled: true
+Lint/LambdaWithoutLiteralBlock: # new in 1.8
+  Enabled: true
+Lint/LiteralAssignmentInCondition: # new in 1.58
+  Enabled: true
+Lint/MixedCaseRange: # new in 1.53
+  Enabled: true
+Lint/NoReturnInBeginEndBlocks: # new in 1.2
+  Enabled: true
+Lint/NonAtomicFileOperation: # new in 1.31
+  Enabled: true
+Lint/NumberedParameterAssignment: # new in 1.9
+  Enabled: true
+Lint/OrAssignmentToConstant: # new in 1.9
+  Enabled: true
+Lint/RedundantDirGlobSort: # new in 1.8
+  Enabled: true
+Lint/RedundantRegexpQuantifiers: # new in 1.53
+  Enabled: true
+Lint/RefinementImportMethods: # new in 1.27
+  Enabled: true
+Lint/RequireRangeParentheses: # new in 1.32
+  Enabled: true
+Lint/RequireRelativeSelfPath: # new in 1.22
+  Enabled: true
+Lint/SymbolConversion: # new in 1.9
+  Enabled: true
+Lint/ToEnumArguments: # new in 1.1
+  Enabled: true
+Lint/TripleQuotes: # new in 1.9
+  Enabled: true
+Lint/UnexpectedBlockArity: # new in 1.5
+  Enabled: true
+Lint/UnmodifiedReduceAccumulator: # new in 1.1
+  Enabled: true
+Lint/UselessRescue: # new in 1.43
+  Enabled: true
+Lint/UselessRuby2Keywords: # new in 1.23
+  Enabled: true
+Metrics/CollectionLiteralLength: # new in 1.47
+  Enabled: true
+Naming/BlockForwarding: # new in 1.24
+  Enabled: true
+Security/CompoundHash: # new in 1.28
+  Enabled: true
+Security/IoMethods: # new in 1.22
+  Enabled: true
+Style/ArgumentsForwarding: # new in 1.1
+  Enabled: true
+Style/ArrayIntersect: # new in 1.40
+  Enabled: true
+Style/CollectionCompact: # new in 1.2
+  Enabled: true
+Style/ComparableClamp: # new in 1.44
+  Enabled: true
+Style/ConcatArrayLiterals: # new in 1.41
+  Enabled: true
+Style/DataInheritance: # new in 1.49
+  Enabled: true
+Style/DirEmpty: # new in 1.48
+  Enabled: true
+Style/DocumentDynamicEvalDefinition: # new in 1.1
+  Enabled: true
+Style/EmptyHeredoc: # new in 1.32
+  Enabled: true
+Style/EndlessMethod: # new in 1.8
+  Enabled: true
+Style/EnvHome: # new in 1.29
+  Enabled: true
+Style/ExactRegexpMatch: # new in 1.51
+  Enabled: true
+Style/FetchEnvVar: # new in 1.28
+  Enabled: true
+Style/FileEmpty: # new in 1.48
+  Enabled: true
+Style/FileRead: # new in 1.24
+  Enabled: true
+Style/FileWrite: # new in 1.24
+  Enabled: true
+Style/HashConversion: # new in 1.10
+  Enabled: true
+Style/HashExcept: # new in 1.7
+  Enabled: true
+Style/IfWithBooleanLiteralBranches: # new in 1.9
+  Enabled: true
+Style/InPatternThen: # new in 1.16
+  Enabled: true
+Style/MagicCommentFormat: # new in 1.35
+  Enabled: true
+Style/MapCompactWithConditionalBlock: # new in 1.30
+  Enabled: true
+Style/MapToHash: # new in 1.24
+  Enabled: true
+Style/MapToSet: # new in 1.42
+  Enabled: true
+Style/MinMaxComparison: # new in 1.42
+  Enabled: true
+Style/MultilineInPatternThen: # new in 1.16
+  Enabled: true
+Style/NegatedIfElseCondition: # new in 1.2
+  Enabled: true
+Style/NestedFileDirname: # new in 1.26
+  Enabled: true
+Style/NilLambda: # new in 1.3
+  Enabled: true
+Style/NumberedParameters: # new in 1.22
+  Enabled: true
+Style/NumberedParametersLimit: # new in 1.22
+  Enabled: true
+Style/ObjectThen: # new in 1.28
+  Enabled: true
+Style/OpenStructUse: # new in 1.23
+  Enabled: true
+Style/OperatorMethodCall: # new in 1.37
+  Enabled: true
+Style/QuotedSymbols: # new in 1.16
+  Enabled: true
+Style/RedundantArgument: # new in 1.4
+  Enabled: true
+Style/RedundantArrayConstructor: # new in 1.52
+  Enabled: true
+Style/RedundantConstantBase: # new in 1.40
+  Enabled: true
+Style/RedundantCurrentDirectoryInPath: # new in 1.53
+  Enabled: true
+Style/RedundantDoubleSplatHashBraces: # new in 1.41
+  Enabled: true
+Style/RedundantEach: # new in 1.38
+  Enabled: true
+Style/RedundantFilterChain: # new in 1.52
+  Enabled: true
+Style/RedundantHeredocDelimiterQuotes: # new in 1.45
+  Enabled: true
+Style/RedundantInitialize: # new in 1.27
+  Enabled: true
+Style/RedundantLineContinuation: # new in 1.49
+  Enabled: true
+Style/RedundantRegexpArgument: # new in 1.53
+  Enabled: true
+Style/RedundantRegexpConstructor: # new in 1.52
+  Enabled: true
+Style/RedundantSelfAssignmentBranch: # new in 1.19
+  Enabled: true
+Style/RedundantStringEscape: # new in 1.37
+  Enabled: true
+Style/ReturnNilInPredicateMethodDefinition: # new in 1.53
+  Enabled: true
+Style/SelectByRegexp: # new in 1.22
+  Enabled: true
+Style/SingleLineDoEndBlock: # new in 1.57
+  Enabled: true
+Style/StringChars: # new in 1.12
+  Enabled: true
+Style/SuperWithArgsParentheses: # new in 1.58
+  Enabled: true
+Style/SwapValues: # new in 1.1
+  Enabled: true
+Style/YAMLFileRead: # new in 1.53
+  Enabled: true
+Performance/AncestorsInclude: # new in 1.7
+  Enabled: true
+Performance/BigDecimalWithNumericArgument: # new in 1.7
+  Enabled: true
+Performance/BlockGivenWithExplicitBlock: # new in 1.9
+  Enabled: true
+Performance/CollectionLiteralInLoop: # new in 1.8
+  Enabled: true
+Performance/ConcurrentMonotonicTime: # new in 1.12
+  Enabled: true
+Performance/ConstantRegexp: # new in 1.9
+  Enabled: true
+Performance/MapCompact: # new in 1.11
+  Enabled: true
+Performance/MapMethodChain: # new in 1.19
+  Enabled: true
+Performance/MethodObjectAsBlock: # new in 1.9
+  Enabled: true
+Performance/RedundantEqualityComparisonBlock: # new in 1.10
+  Enabled: true
+Performance/RedundantSortBlock: # new in 1.7
+  Enabled: true
+Performance/RedundantSplitRegexpArgument: # new in 1.10
+  Enabled: true
+Performance/RedundantStringChars: # new in 1.7
+  Enabled: true
+Performance/ReverseFirst: # new in 1.7
+  Enabled: true
+Performance/SortReverse: # new in 1.7
+  Enabled: true
+Performance/Squeeze: # new in 1.7
+  Enabled: true
+Performance/StringIdentifierArgument: # new in 1.13
+  Enabled: true
+Performance/StringInclude: # new in 1.7
+  Enabled: true
+Performance/Sum: # new in 1.8
+  Enabled: true
diff --git a/Gemfile b/Gemfile
index b5aed45..2febd8f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -11,6 +11,6 @@ gem 'simplecov', '~> 0.19.0'
 gem 'multipart-parser', '~> 0.1.1'
 gem 'webmock', '~> 3.4'
 
-gem 'rubocop', '~> 0.91.1'
+gem 'rubocop', '~> 1.59.0'
 gem 'rubocop-packaging', '~> 0.5'
-gem 'rubocop-performance', '~> 1.0'
+gem 'rubocop-performance', '~> 1.20'
diff --git a/faraday-excon.gemspec b/faraday-excon.gemspec
index b4b737e..3cf3e28 100644
--- a/faraday-excon.gemspec
+++ b/faraday-excon.gemspec
@@ -16,12 +16,13 @@ Gem::Specification.new do |spec|
   spec.required_ruby_version = Gem::Requirement.new('>= 2.6.0')
 
   spec.metadata['homepage_uri'] = spec.homepage
+  spec.metadata['rubygems_mfa_required'] = 'true'
   spec.metadata['source_code_uri'] = 'https://github.com/lostisland/faraday-excon'
   spec.metadata['changelog_uri'] = "https://github.com/lostisland/faraday-excon/releases/tag/v#{spec.version}"
 
   spec.files = Dir.glob('lib/**/*') + %w[README.md LICENSE.md]
   spec.require_paths = ['lib']
 
-  spec.add_dependency 'excon', '>= 0.27.4'
+  spec.add_dependency 'excon', '>= 0.109.0'
   spec.add_dependency 'faraday', '~> 2.0'
 end
diff --git a/lib/faraday/adapter/excon.rb b/lib/faraday/adapter/excon.rb
index be88c07..7abce9b 100644
--- a/lib/faraday/adapter/excon.rb
+++ b/lib/faraday/adapter/excon.rb
@@ -5,9 +5,10 @@ class Adapter
     # Excon adapter.
     class Excon < Faraday::Adapter
       def build_connection(env)
-        if @connection_options[:persistent]
-          return @connection if defined? @connection
+        if @connection_options[:persistent] && defined?(@connection)
+          return @connection
         end
+
         opts = opts_from_env(env)
 
         # remove path & query when creating connection