diff --git a/swift-define b/swift-define
index 5c7b443..cb3e07c 100644
--- a/swift-define
+++ b/swift-define
@@ -10,8 +10,8 @@ SWIFT_NATIVE_PATH="${SWIFT_NATIVE_PATH:=/usr/bin}"
 SWIFT_LLVM_DIR="${SWIFT_LLVM_DIR:=/usr/lib/llvm-12}"
 SWIFT_BUILD_CONFIGURATION="${SWIFT_BUILD_CONFIGURATION:=Release}"
 SWIFTPM_CONFIGURATION="${SWIFTPM_CONFIGURATION:=release}"
-SWIFT_PACKAGE_SRCDIR=$SRC_ROOT/swift-hello
-SWIFT_PACKAGE_BUILDDIR=$SRC_ROOT/build/swift-hello
+SWIFT_PACKAGE_SRCDIR="${SWIFT_PACKAGE_SRCDIR:=$SRC_ROOT/swift-hello}"
+SWIFT_PACKAGE_BUILDDIR="${SWIFT_PACKAGE_BUILDDIR:=$SRC_ROOT/build/swift-hello}"
 
 # Build Paths
 SWIFT_SRCDIR=$SRC_ROOT/downloads/swift-swift-${SWIFT_VERSION}-RELEASE