diff --git a/build.sh b/build.sh
index 0a09982..ed15deb 100755
--- a/build.sh
+++ b/build.sh
@@ -196,6 +196,12 @@ output_dir="$script_dir/$output"
 
 ## PREREQUISITES CHECK
 
+# Check for bash >= 4.0
+if [ "${BASH_VERSINFO:-0}" -lt 4 ]; then
+  log "bash >= 4.0 is required. Aborting."
+  exit 1
+fi
+
 # Check for dotnet
 command_exists dotnet || {
   log "dotnet is required but it's not installed or not in PATH. Aborting."
@@ -301,4 +307,10 @@ if [ "$BUILD_IOS" = true ]; then
   build_ios
 fi
 
-echo "Build completed. See $log_file for details."
+# Check last command exit code
+if [ $? -ne 0 ]; then
+  log "Build failed. See $log_file for details."
+  exit 1
+else
+  log "Finished building. See $log_file for details."
+fi