diff --git a/Package.resolved b/Package.resolved
index d25ff1c..bc4e19a 100644
--- a/Package.resolved
+++ b/Package.resolved
@@ -1,4 +1,5 @@
 {
+  "originHash" : "15814f79ce243f84480670d719bb28981b0b3c450df10d2fcb91f042bcd175bb",
   "pins" : [
     {
       "identity" : "swift-custom-dump",
@@ -32,8 +33,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/swiftlang/swift-syntax",
       "state" : {
-        "revision" : "64889f0c732f210a935a0ad7cda38f77f876262d",
-        "version" : "509.1.1"
+        "revision" : "0687f71944021d616d34d922343dcef086855920",
+        "version" : "600.0.1"
       }
     },
     {
@@ -46,5 +47,5 @@
       }
     }
   ],
-  "version" : 2
+  "version" : 3
 }
diff --git a/Package.swift b/Package.swift
index ca616c4..159b7ba 100644
--- a/Package.swift
+++ b/Package.swift
@@ -1,4 +1,4 @@
-// swift-tools-version: 5.9
+// swift-tools-version: 6.0
 import CompilerPluginSupport
 import PackageDescription
 
@@ -19,7 +19,7 @@ let package = Package(
     ),
   ],
   dependencies: [
-    .package(url: "https://github.com/swiftlang/swift-syntax", from: "509.1.0"),
+    .package(url: "https://github.com/swiftlang/swift-syntax", "509.1.0"..<"603.0.0"),
     // We only really need swift-macro-testing 0.3.0 or newer but 0.4.0 is required to compile due
     // to breaking changes in swift-snapshot-testing.
     .package(url: "https://github.com/pointfreeco/swift-macro-testing.git", from: "0.4.0"),