diff --git a/start.sh b/start.sh
index 8bd6661..c698d81 100755
--- a/start.sh
+++ b/start.sh
@@ -14,7 +14,6 @@ if [ $? -ne 1 ]; then
 fi
 
 # Setup for Darwin.
-HOST_FLAGS=""
 uname -a | grep Darwin > /dev/null
 if [ $? -ne 1 ]; then
 	export CC=gcc-11
@@ -25,8 +24,6 @@ if [ $? -ne 1 ]; then
 	alias gcc="gcc-11"
 	alias g++="g++-11"
 	alias sed="gsed"
-	HOST_FLAGS="-DHOST_DARWIN"
-	echo Detected host Darwin.
 fi
 
 # Check that the source code is valid.
@@ -72,6 +69,6 @@ if [ $? -ne 0 ]; then
 fi
 
 # Compile and run Build.
-gcc -o bin/build -g util/build.c -pthread -DPARALLEL_BUILD -D${ES_TARGET-TARGET_X86_64} $HOST_FLAGS \
+gcc -o bin/build -g util/build.c -pthread -DPARALLEL_BUILD -D${ES_TARGET-TARGET_X86_64} \
 		-Wall -Wextra -Wno-format-security -Wno-format-overflow -Wno-missing-field-initializers -Wno-unused-function -Wno-format-truncation \
 	&& bin/build "$@"
diff --git a/util/build.c b/util/build.c
index 9a1d110..580e186 100644
--- a/util/build.c
+++ b/util/build.c
@@ -398,7 +398,7 @@ void Build(int optimise, bool compile) {
 	}
 #endif
 
-#ifndef HOST_DARWIN
+#ifndef __APPLE__
 	CallSystem("ctags -R "
 			"--exclude=old/* "
 			"--exclude=root/* "
@@ -642,7 +642,7 @@ void BuildCrossCompiler() {
 		if (CallSystem("which sed > /dev/null 2>&1")) { printf("Error: Missing sed.\n"); missingPackages = true; }
 		if (CallSystem("which awk > /dev/null 2>&1")) { printf("Error: Missing awk.\n"); missingPackages = true; }
 
-#ifdef HOST_DARWIN
+#ifdef __APPLE__
 		if (CallSystem("gcc -L/opt/homebrew/lib -lmpc 2>&1 | grep -i undefined > /dev/null")) { printf("Error: Missing GNU MPC.\n"); missingLibraries = true; }
 		if (CallSystem("gcc -L/opt/homebrew/lib -lmpfr 2>&1 | grep -i undefined > /dev/null")) { printf("Error: Missing GNU MPFR.\n"); missingLibraries = true; }
 		if (CallSystem("gcc -L/opt/homebrew/lib -lgmp 2>&1 | grep -i undefined > /dev/null")) { printf("Error: Missing GNU GMP.\n"); missingLibraries = true; }
@@ -1227,8 +1227,8 @@ void GetSource(const char *parameters, const char *checksum) {
 
 	free(alternateURL);
 
-#ifdef HOST_DARWIN
-#define SHA256SUM "sha256 -a 256"
+#ifdef __APPLE__
+#define SHA256SUM "shasum -a 256"
 #else
 #define SHA256SUM "sha256sum"
 #endif