diff --git a/Xcode/Sources/HttpServerIO.swift b/Xcode/Sources/HttpServerIO.swift
index 65c6e95a..9969abdb 100644
--- a/Xcode/Sources/HttpServerIO.swift
+++ b/Xcode/Sources/HttpServerIO.swift
@@ -100,11 +100,11 @@ open class HttpServerIO {
     public func stop() {
         guard self.operating else { return }
         self.state = .stopping
-        // Shutdown connected peers because they can live in 'keep-alive' or 'websocket' loops.
-        for socket in self.sockets {
-            socket.close()
-        }
         self.queue.sync {
+            // Shutdown connected peers because they can live in 'keep-alive' or 'websocket' loops.
+            for socket in self.sockets {
+                socket.close()
+            }
             self.sockets.removeAll(keepingCapacity: true)
         }
         socket.close()
diff --git a/Xcode/Tests/FilesTests.swift b/Xcode/Tests/FilesTests.swift
index 1f884844..2c82e5d8 100644
--- a/Xcode/Tests/FilesTests.swift
+++ b/Xcode/Tests/FilesTests.swift
@@ -55,7 +55,7 @@ class FilesTests: XCTestCase {
         let closure = shareFile(temporaryDirectoryURL.appendingPathComponent("does_not_exist").path)
         let result = closure(request)
 
-        XCTAssert(result == .notFound)
+        XCTAssert(result == .notFound())
     }
 
     func testShareFilesFromDirectory() {
@@ -77,7 +77,7 @@ class FilesTests: XCTestCase {
         let closure = shareFilesFromDirectory(temporaryDirectoryURL.path)
         let result = closure(request)
 
-        XCTAssert(result == .notFound)
+        XCTAssert(result == .notFound())
     }
     
     func testDirectoryBrowser() {
@@ -95,6 +95,6 @@ class FilesTests: XCTestCase {
         let closure = directoryBrowser(temporaryDirectoryURL.path)
         let result = closure(request)
 
-        XCTAssert(result == .notFound)
+        XCTAssert(result == .notFound())
     }
 }