diff --git a/core/config.mk b/core/config.mk
index b3f3d3662..35a289aae 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -178,6 +178,9 @@ endef
 # Set common values
 # ###############################################################
 
+# Initialize SOONG_CONFIG_NAMESPACES so that it isn't recursive.
+SOONG_CONFIG_NAMESPACES :=
+
 # Set the extensions used for various packages
 COMMON_PACKAGE_SUFFIX := .zip
 COMMON_JAVA_PACKAGE_SUFFIX := .jar
diff --git a/core/main.mk b/core/main.mk
index 4f59076c3..16e70ebc2 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -52,6 +52,10 @@ ifneq ($(filter $(dont_bother_goals), $(MAKECMDGOALS)),)
 dont_bother := true
 endif
 
+.KATI_READONLY := SOONG_CONFIG_NAMESPACES
+.KATI_READONLY := $(foreach n,$(SOONG_CONFIG_NAMESPACES),SOONG_CONFIG_$(n))
+.KATI_READONLY := $(foreach n,$(SOONG_CONFIG_NAMESPACES),$(foreach k,$(SOONG_CONFIG_$(n)),SOONG_CONFIG_$(n)_$(k)))
+
 include $(SOONG_MAKEVARS_MK)
 
 include $(BUILD_SYSTEM)/clang/config.mk
diff --git a/core/soong_config.mk b/core/soong_config.mk
index bf40fe345..ab493d916 100644
--- a/core/soong_config.mk
+++ b/core/soong_config.mk
@@ -137,7 +137,15 @@ $(call add_json_list, NamespacesToExport,                $(PRODUCT_SOONG_NAMESPA
 
 $(call add_json_list, PgoAdditionalProfileDirs,          $(PGO_ADDITIONAL_PROFILE_DIRS))
 
-_contents := $(subst $(comma)$(newline)__SV_END,$(newline)}$(newline),$(_contents)__SV_END)
+_contents := $(_contents)    "VendorVars": {$(newline)
+$(foreach namespace,$(SOONG_CONFIG_NAMESPACES),\
+  $(eval _contents := $$(_contents)        "$(namespace)": {$$(newline)) \
+  $(foreach key,$(SOONG_CONFIG_$(namespace)),\
+    $(eval _contents := $$(_contents)            "$(key)": "$(SOONG_CONFIG_$(namespace)_$(key))",$$(newline)))\
+  $(eval _contents := $$(_contents)$(if $(strip $(SOONG_CONFIG_$(namespace))),__SV_END)        },$$(newline)))
+_contents := $(_contents)$(if $(strip $(SOONG_CONFIG_NAMESPACES)),__SV_END)    },$(newline)
+
+_contents := $(subst $(comma)$(newline)__SV_END,$(newline),$(_contents)__SV_END}$(newline))
 
 $(file >$(SOONG_VARIABLES).tmp,$(_contents))