diff --git a/Package.resolved b/Package.resolved
index c4f9794..6340fa4 100644
--- a/Package.resolved
+++ b/Package.resolved
@@ -5,8 +5,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-syntax.git",
       "state" : {
-        "revision" : "165fc6d22394c1168ff76ab5d951245971ef07e5",
-        "version" : "509.0.0-swift-DEVELOPMENT-SNAPSHOT-2023-06-05-a"
+        "revision" : "057bdfb4632cc758973d46efaf98e43d07ee4bdb",
+        "version" : "509.0.0-swift-DEVELOPMENT-SNAPSHOT-2023-08-28-a"
       }
     }
   ],
diff --git a/Package.swift b/Package.swift
index 41f07bb..c1cf164 100644
--- a/Package.swift
+++ b/Package.swift
@@ -13,6 +13,7 @@ let package = Package(
       name: "ExtractCaseValue",
       targets: ["ExtractCaseValue"]
     ),
+    .library(name: "ExtractCaseValueTypes", targets: ["ExtractCaseValueTypes"]),
     .executable(
       name: "ExtractCaseValueClient",
       targets: ["ExtractCaseValueClient"]
@@ -20,7 +21,7 @@ let package = Package(
   ],
   dependencies: [
     // Depend on the latest Swift 5.9 prerelease of SwiftSyntax
-    .package(url: "https://github.com/apple/swift-syntax.git", from: "509.0.0-swift-5.9-DEVELOPMENT-SNAPSHOT-2023-04-25-b")
+    .package(url: "https://github.com/apple/swift-syntax.git", from: "509.0.0-swift-DEVELOPMENT-SNAPSHOT-2023-08-28-a")
   ],
   targets: [
     // Targets are the basic building blocks of a package, defining a module or a test suite.
@@ -30,12 +31,16 @@ let package = Package(
       name: "ExtractCaseValueMacros",
       dependencies: [
         .product(name: "SwiftSyntaxMacros", package: "swift-syntax"),
-        .product(name: "SwiftCompilerPlugin", package: "swift-syntax")
+        .product(name: "SwiftCompilerPlugin", package: "swift-syntax"),
+        "ExtractCaseValueTypes"
       ]
     ),
 
     // Library that exposes a macro as part of its API, which is used in client programs.
-    .target(name: "ExtractCaseValue", dependencies: ["ExtractCaseValueMacros"]),
+    .target(name: "ExtractCaseValue", dependencies: ["ExtractCaseValueMacros", "ExtractCaseValueTypes"]),
+    .target(name: "ExtractCaseValueTypes", dependencies: [
+        .product(name: "SwiftSyntax", package: "swift-syntax"),
+    ]),
 
     // A client of the library, which is able to use the macro in its own code.
     .executableTarget(name: "ExtractCaseValueClient", dependencies: ["ExtractCaseValue"]),
diff --git a/Sources/ExtractCaseValue/ExtractCaseValue.swift b/Sources/ExtractCaseValue/ExtractCaseValue.swift
index f3280f8..54b2793 100644
--- a/Sources/ExtractCaseValue/ExtractCaseValue.swift
+++ b/Sources/ExtractCaseValue/ExtractCaseValue.swift
@@ -1,4 +1,4 @@
-import ExtractCaseValueMacros
+import ExtractCaseValueTypes
 
 /// A macro that extracts an associated value from enum cases using a default value if
 /// extraction is not possible.
diff --git a/Sources/ExtractCaseValueMacros/CaseExtractionKind.swift b/Sources/ExtractCaseValueMacros/CaseExtractionKind.swift
index 4c90b2d..497d32c 100644
--- a/Sources/ExtractCaseValueMacros/CaseExtractionKind.swift
+++ b/Sources/ExtractCaseValueMacros/CaseExtractionKind.swift
@@ -1,40 +1,27 @@
 import SwiftSyntax
-
-/// The available kinds of case value extractions.
-public enum CaseExtractionKind {
-  /// Extract a value at a position in the associated values.
-  case position(Int)
-
-  /// Extract a value with a certain name.
-  case associatedValueName(String)
-
-  /// Extract the first value with a matching type.
-  case firstMatchingType
-
-  public static let `default` = Self.firstMatchingType
-}
+import ExtractCaseValueTypes
 
 extension CaseExtractionKind {
-  init?(expr: ExprSyntax) {
-    guard
-      let functionCall = expr.as(FunctionCallExprSyntax.self),
-      let memberAccessExpr = functionCall.calledExpression.as(MemberAccessExprSyntax.self)
-    else { return nil }
+    init?(expr: ExprSyntax) {
+        guard
+            let functionCall = expr.as(FunctionCallExprSyntax.self),
+            let memberAccessExpr = functionCall.calledExpression.as(MemberAccessExprSyntax.self)
+        else { return nil }
 
-    let firstIntArgument = (functionCall.argumentList.first?.expression.as(IntegerLiteralExprSyntax.self)?.digits.text).flatMap(Int.init)
-    let firstStringArgument = functionCall.argumentList.first?.expression.stringLiteralSegment
+        let firstIntArgument = (functionCall.argumentList.first?.expression.as(IntegerLiteralExprSyntax.self)?.digits.text).flatMap(Int.init)
+        let firstStringArgument = functionCall.argumentList.first?.expression.stringLiteralSegment
 
-    switch memberAccessExpr.name.text {
-    case "position" :
-      guard let position = firstIntArgument else { return nil }
-      self = .position(position)
-    case "associatedValueName":
-      guard let name = firstStringArgument?.content.text else { return nil }
-      self = .associatedValueName(name)
-    case "firstMatchingType":
-      self = .firstMatchingType
-    default:
-      return nil
+        switch memberAccessExpr.name.text {
+        case "position" :
+            guard let position = firstIntArgument else { return nil }
+            self = .position(position)
+        case "associatedValueName":
+            guard let name = firstStringArgument?.content.text else { return nil }
+            self = .associatedValueName(name)
+        case "firstMatchingType":
+            self = .firstMatchingType
+        default:
+            return nil
+        }
     }
-  }
 }
diff --git a/Sources/ExtractCaseValueMacros/ExtractCaseValueMacro.swift b/Sources/ExtractCaseValueMacros/ExtractCaseValueMacro.swift
index 347d2ae..d1e3290 100644
--- a/Sources/ExtractCaseValueMacros/ExtractCaseValueMacro.swift
+++ b/Sources/ExtractCaseValueMacros/ExtractCaseValueMacro.swift
@@ -2,6 +2,7 @@ import SwiftDiagnostics
 import SwiftSyntax
 import SwiftSyntaxBuilder
 import SwiftSyntaxMacros
+import ExtractCaseValueTypes
 
 // Argument labels
 let caseParamExtractionPropertyNameArgumentLabel = "name"
@@ -98,7 +99,7 @@ extension ExtractCaseValueMacro: MemberMacro {
     let elements = caseDecls.flatMap(\.elements)
 
     // infer access modifier from enum
-    let access = enumDecl.modifiers?.first(where: \.isNeededAccessLevelModifier)
+    let access = enumDecl.modifiers.first(where: \.isNeededAccessLevelModifier)
 
     var switchCaseSyntaxes: [SwitchCaseSyntax] = []
 
diff --git a/Sources/ExtractCaseValueTypes/CaseExtractionKind.swift b/Sources/ExtractCaseValueTypes/CaseExtractionKind.swift
new file mode 100644
index 0000000..8ce02ff
--- /dev/null
+++ b/Sources/ExtractCaseValueTypes/CaseExtractionKind.swift
@@ -0,0 +1,23 @@
+//
+//  CaseExtractionKind.swift
+//  
+//
+//  Created by Tomas Harkema on 02/09/2023.
+//
+
+import Foundation
+
+/// The available kinds of case value extractions.
+public enum CaseExtractionKind {
+    /// Extract a value at a position in the associated values.
+    case position(Int)
+
+    /// Extract a value with a certain name.
+    case associatedValueName(String)
+
+    /// Extract the first value with a matching type.
+    case firstMatchingType
+
+    public static let `default` = Self.firstMatchingType
+}
+