diff --git a/Package.swift b/Package.swift
index bec8c39..1c14b1d 100644
--- a/Package.swift
+++ b/Package.swift
@@ -1,4 +1,4 @@
-// swift-tools-version:4.0
+// swift-tools-version:4.1
 import PackageDescription
 
 let package = Package(
diff --git a/Sources/URLEncodedForm/Data/URLEncodedFormParser.swift b/Sources/URLEncodedForm/Data/URLEncodedFormParser.swift
index b4e4634..358c864 100644
--- a/Sources/URLEncodedForm/Data/URLEncodedFormParser.swift
+++ b/Sources/URLEncodedForm/Data/URLEncodedFormParser.swift
@@ -209,7 +209,7 @@ private extension Data {
 
 fileprivate extension Array {
     /// Accesses an array index or returns `nil` if the array isn't long enough.
-    fileprivate subscript(safe index: Int) -> Element? {
+    subscript(safe index: Int) -> Element? {
         guard index < count else {
             return nil
         }