diff --git a/Makefile b/Makefile
index a76e0db..49cf661 100644
--- a/Makefile
+++ b/Makefile
@@ -55,7 +55,6 @@ clean:
 build/llvm.BUILT:
 	mkdir -p build/llvm
 	cd build/llvm && cmake -G Ninja \
-		-DCMAKE_MODULE_PATH=$(ROOT_DIR)/cmake \
 		-DCMAKE_BUILD_TYPE=MinSizeRel \
 		-DCMAKE_INSTALL_PREFIX=$(PREFIX) \
 		-DLLVM_TARGETS_TO_BUILD=WebAssembly \
@@ -95,8 +94,8 @@ build/wasi-libc.BUILT: build/llvm.BUILT
 build/compiler-rt.BUILT: build/llvm.BUILT
 	# Create an empty library so that cmake's configure checks which
 	# run the compiler to see if it produces working binaries succeed.
-	mkdir -p  $(PREFIX)/lib/clang/$(CLANG_VERSION)/lib/wasi
-	$(AR) cr $(PREFIX)/lib/clang/$(CLANG_VERSION)/lib/wasi/libclang_rt.builtins-wasm32.a
+	mkdir -p  $(BUILD_PREFIX)/lib/clang/$(CLANG_VERSION)/lib/wasi
+	$(AR) cr $(BUILD_PREFIX)/lib/clang/$(CLANG_VERSION)/lib/wasi/libclang_rt.builtins-wasm32.a
 	# Do the build, and install it.
 	mkdir -p build/compiler-rt
 	cd build/compiler-rt && cmake -G Ninja \
@@ -148,9 +147,9 @@ LIBCXX_CMAKE_FLAGS = \
 build/libcxx.BUILT: build/llvm.BUILT build/compiler-rt.BUILT build/wasi-libc.BUILT
 	# Create an empty library so that cmake's configure checks which
 	# run the compiler to see if it produces working binaries succeed.
-	mkdir -p  $(PREFIX)/lib/clang/$(CLANG_VERSION)/lib/wasi
-	$(AR) cr $(PREFIX)/share/wasi-sysroot/lib/wasm32-wasi/libc++.a
-	$(AR) cr $(PREFIX)/share/wasi-sysroot/lib/wasm32-wasi/libc++abi.a
+	mkdir -p  $(BUILD_PREFIX)/lib/clang/$(CLANG_VERSION)/lib/wasi
+	$(AR) cr $(BUILD_PREFIX)/share/wasi-sysroot/lib/wasm32-wasi/libc++.a
+	$(AR) cr $(BUILD_PREFIX)/share/wasi-sysroot/lib/wasm32-wasi/libc++abi.a
 	# Do the build.
 	mkdir -p build/libcxx
 	cd build/libcxx && cmake -G Ninja $(LIBCXX_CMAKE_FLAGS) \
@@ -193,8 +192,8 @@ LIBCXXABI_CMAKE_FLAGS = \
 build/libcxxabi.BUILT: build/libcxx.BUILT build/llvm.BUILT
 	# Create an empty library so that cmake's configure checks which
 	# run the compiler to see if it produces working binaries succeed.
-	mkdir -p  $(PREFIX)/lib/clang/$(CLANG_VERSION)/lib/wasi
-	$(AR) cr $(PREFIX)/share/wasi-sysroot/lib/wasm32-wasi/libc++.a
+	mkdir -p  $(BUILD_PREFIX)/lib/clang/$(CLANG_VERSION)/lib/wasi
+	$(AR) cr $(BUILD_PREFIX)/share/wasi-sysroot/lib/wasm32-wasi/libc++.a
 	# Do the build.
 	mkdir -p build/libcxxabi
 	cd build/libcxxabi && cmake -G Ninja $(LIBCXXABI_CMAKE_FLAGS) \