diff --git a/buildroot/share/PlatformIO/scripts/common-cxxflags.py b/buildroot/share/PlatformIO/scripts/common-cxxflags.py
index 3e75434ee7..ee2afb1d26 100644
--- a/buildroot/share/PlatformIO/scripts/common-cxxflags.py
+++ b/buildroot/share/PlatformIO/scripts/common-cxxflags.py
@@ -10,3 +10,13 @@ env.Append(CXXFLAGS=[
   #"-Wno-maybe-uninitialized",
   #"-Wno-sign-compare"
 ])
+
+# Useful for JTAG debugging
+#
+# It will separe release and debug build folders. 
+# It useful when we need keep two live versions: one debug, for debugging, 
+# other release, for flashing.
+# Without this, PIO will recompile everything twice for any small change.
+# 
+if env.GetBuildType() == "debug":
+	env['BUILD_DIR'] = '$PROJECT_BUILD_DIR/$PIOENV/debug'