diff --git a/.gitmodules b/.gitmodules
index 97c0a85..333a85e 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,6 +1,6 @@
 [submodule "Sources/ChessKitEngineCore/Engines/Stockfish"]
 	path = Sources/ChessKitEngineCore/Engines/Stockfish
-	url = https://github.com/official-stockfish/Stockfish.git
+	url = https://github.com/chesskit-app/Stockfish.git
 [submodule "Sources/ChessKitEngineCore/Engines/lc0"]
 	path = Sources/ChessKitEngineCore/Engines/lc0
 	url = https://github.com/chesskit-app/lc0.git
diff --git a/Package.swift b/Package.swift
index 196488a..6ed21ab 100644
--- a/Package.swift
+++ b/Package.swift
@@ -30,7 +30,12 @@ let package = Package(
                 .headerSearchPath("Engines/lc0/src"),
                 .headerSearchPath("Engines/lc0/subprojects/eigen-3.4.0"),
                 .define("NNUE_EMBEDDING_OFF"),
-                .define("NO_PEXT")
+                .define("NO_PEXT"),
+                .unsafeFlags([
+                    // suppress Stockfish warnings
+                    "-Wno-deprecated-declarations",
+                    "-Wno-shorten-64-to-32"
+                ])
             ],
             linkerSettings: [
                 .linkedLibrary("z")
@@ -40,8 +45,7 @@ let package = Package(
             name: "ChessKitEngineTests",
             dependencies: ["ChessKitEngine"],
             resources: [
-                .copy("EngineTests/Resources/192x15_network"),
-                .copy("EngineTests/Resources/nn-1337b1adec5b.nnue")
+                .copy("EngineTests/Resources/192x15_network")
             ]
         )
     ],
diff --git a/Resources/nn-1337b1adec5b.nnue b/Resources/nn-1337b1adec5b.nnue
deleted file mode 100644
index dde91cb..0000000
Binary files a/Resources/nn-1337b1adec5b.nnue and /dev/null differ
diff --git a/Sources/ChessKitEngine/Resources/nn-baff1ede1f90.nnue b/Sources/ChessKitEngine/Resources/nn-baff1ede1f90.nnue
deleted file mode 100644
index 6469b88..0000000
Binary files a/Sources/ChessKitEngine/Resources/nn-baff1ede1f90.nnue and /dev/null differ
diff --git a/Sources/ChessKitEngineCore/Engines/Extensions/lc0+engine.cpp b/Sources/ChessKitEngineCore/Engines/Extensions/lc0+engine.cpp
index 89862e0..631d058 100644
--- a/Sources/ChessKitEngineCore/Engines/Extensions/lc0+engine.cpp
+++ b/Sources/ChessKitEngineCore/Engines/Extensions/lc0+engine.cpp
@@ -3,10 +3,10 @@
 //  ChessKitEngine
 //
 
-#import "lc0+engine.h"
+#include "lc0+engine.h"
 
-#import "../lc0/src/chess/board.h"
-#import "../lc0/src/engine.h"
+#include "../lc0/src/chess/board.h"
+#include "../lc0/src/engine.h"
 
 using namespace lczero;
 
diff --git a/Sources/ChessKitEngineCore/Engines/Extensions/lc0+engine.h b/Sources/ChessKitEngineCore/Engines/Extensions/lc0+engine.h
index 06dca29..11835a5 100644
--- a/Sources/ChessKitEngineCore/Engines/Extensions/lc0+engine.h
+++ b/Sources/ChessKitEngineCore/Engines/Extensions/lc0+engine.h
@@ -6,8 +6,8 @@
 #ifndef lc0_engine_h
 #define lc0_engine_h
 
-#import "engine.h"
-#import <string>
+#include "engine.h"
+#include <string>
 
 /// LeelaChessZero (Lc0) implementation of `Engine`.
 class Lc0Engine: public Engine {
diff --git a/Sources/ChessKitEngineCore/Engines/Extensions/stockfish+engine.cpp b/Sources/ChessKitEngineCore/Engines/Extensions/stockfish+engine.cpp
index 42ce36e..7f0f4d4 100644
--- a/Sources/ChessKitEngineCore/Engines/Extensions/stockfish+engine.cpp
+++ b/Sources/ChessKitEngineCore/Engines/Extensions/stockfish+engine.cpp
@@ -3,14 +3,16 @@
 //  ChessKitEngine
 //
 
-#import "stockfish+engine.h"
-#import "../Stockfish/src/_main.h"
-#import "../Stockfish/src/thread.h"
+#include "stockfish+engine.h"
+#include "../Stockfish/src/_main.h"
+#include "../Stockfish/src/thread.h"
 
 using namespace Stockfish;
 
 void StockfishEngine::initialize() {
-    _main(1, (char* []){""});
+    char empty[] = "";
+    char* argv[] = { empty };
+    _main(1, argv);
 }
 
 void StockfishEngine::deinitialize() {
diff --git a/Sources/ChessKitEngineCore/Engines/Extensions/stockfish+engine.h b/Sources/ChessKitEngineCore/Engines/Extensions/stockfish+engine.h
index c9f909e..8af7333 100644
--- a/Sources/ChessKitEngineCore/Engines/Extensions/stockfish+engine.h
+++ b/Sources/ChessKitEngineCore/Engines/Extensions/stockfish+engine.h
@@ -6,8 +6,8 @@
 #ifndef stockfish_engine_h
 #define stockfish_engine_h
 
-#import "engine.h"
-#import <string>
+#include "engine.h"
+#include <string>
 
 /// Stockfish implementation of `Engine`.
 class StockfishEngine: public Engine {
diff --git a/Sources/ChessKitEngineCore/Engines/Stockfish b/Sources/ChessKitEngineCore/Engines/Stockfish
index e67cc97..63092f0 160000
--- a/Sources/ChessKitEngineCore/Engines/Stockfish
+++ b/Sources/ChessKitEngineCore/Engines/Stockfish
@@ -1 +1 @@
-Subproject commit e67cc979fd2c0e66dfc2b2f2daa0117458cfc462
+Subproject commit 63092f02082518e285b3741a1a5b48b3bfda2096
diff --git a/Tests/ChessKitEngineTests/EngineTests/Resources/nn-1337b1adec5b.nnue b/Tests/ChessKitEngineTests/EngineTests/Resources/nn-1337b1adec5b.nnue
deleted file mode 100644
index dde91cb..0000000
Binary files a/Tests/ChessKitEngineTests/EngineTests/Resources/nn-1337b1adec5b.nnue and /dev/null differ