diff --git a/.external-dummy/Kconfig b/.external-dummy/Kconfig
new file mode 100644
index 0000000000..8e28fe6a4b
--- /dev/null
+++ b/.external-dummy/Kconfig
@@ -0,0 +1 @@
+# This is supposed to be empty
diff --git a/.external-dummy/README.md b/.external-dummy/README.md
new file mode 100644
index 0000000000..150147a124
--- /dev/null
+++ b/.external-dummy/README.md
@@ -0,0 +1,2 @@
+This directory exists to hold an empty Kconfig which is used
+when no nuttx/external is present.
diff --git a/.gitignore b/.gitignore
index cdb922cf88..44615e658b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -46,3 +46,4 @@
 core
 Make*.dep
 uImage
+/external
diff --git a/Kconfig b/Kconfig
index 3a4bce3300..331e3bde4a 100644
--- a/Kconfig
+++ b/Kconfig
@@ -1826,3 +1826,15 @@ endmenu
 menu "Application Configuration"
 source "$APPSDIR/Kconfig"
 endmenu
+
+# Support optionally including external code
+# into the OS build. EXTERNALDIR will be used
+# to either point to 'nuttx/external' or
+# 'nuttx/.external-dummy', if 'nuttx/external'
+# does not contain a Kconfig file
+
+config EXTERNALDIR
+        string
+        option env="EXTERNALDIR"
+
+source "$EXTERNALDIR/Kconfig"
diff --git a/tools/Directories.mk b/tools/Directories.mk
index f6c0602947..a033dff587 100644
--- a/tools/Directories.mk
+++ b/tools/Directories.mk
@@ -72,6 +72,11 @@ endif
 
 KERNDEPDIRS += sched drivers boards $(ARCH_SRC)
 KERNDEPDIRS += fs binfmt
+
+ifeq ($(EXTERNALDIR),external)
+  KERNDEPDIRS += external
+endif
+
 CONTEXTDIRS = boards fs $(APPDIR)
 CLEANDIRS += pass1
 
diff --git a/tools/FlatLibs.mk b/tools/FlatLibs.mk
index 657481fe2a..c7669a6936 100644
--- a/tools/FlatLibs.mk
+++ b/tools/FlatLibs.mk
@@ -48,6 +48,12 @@ USERLIBS =
 
 NUTTXLIBS += staging$(DELIM)libdrivers$(LIBEXT)
 
+# External code support
+
+ifeq ($(EXTERNALDIR),external)
+  NUTTXLIBS += staging$(DELIM)libexternal$(LIBEXT)
+endif
+
 # Add libraries for board support
 
 NUTTXLIBS += staging$(DELIM)libboards$(LIBEXT)
diff --git a/tools/KernelLibs.mk b/tools/KernelLibs.mk
index e50da99f08..8dbb7151f2 100644
--- a/tools/KernelLibs.mk
+++ b/tools/KernelLibs.mk
@@ -47,6 +47,12 @@ USERLIBS =
 
 NUTTXLIBS += staging$(DELIM)libdrivers$(LIBEXT)
 
+# External code support
+
+ifeq ($(EXTERNALDIR),external)
+  NUTTXLIBS += staging$(DELIM)libexternal$(LIBEXT)
+endif
+
 # Add libraries for board support
 
 NUTTXLIBS += staging$(DELIM)libboards$(LIBEXT)
diff --git a/tools/LibTargets.mk b/tools/LibTargets.mk
index b5c4e980f3..e04a6a62c6 100644
--- a/tools/LibTargets.mk
+++ b/tools/LibTargets.mk
@@ -106,6 +106,12 @@ drivers$(DELIM)libdrivers$(LIBEXT): pass2dep
 staging$(DELIM)libdrivers$(LIBEXT): drivers$(DELIM)libdrivers$(LIBEXT)
 	$(Q) $(call INSTALL_LIB,$<,$@)
 
+external$(DELIM)libexternal$(LIBEXT): pass2dep
+	$(Q) $(MAKE) -C external libexternal$(LIBEXT) EXTRAFLAGS="$(KDEFINE) $(EXTRAFLAGS)"
+
+staging$(DELIM)libexternal$(LIBEXT): external$(DELIM)libexternal$(LIBEXT)
+	$(Q) $(call INSTALL_LIB,$<,$@)
+
 binfmt$(DELIM)libbinfmt$(LIBEXT): pass2dep
 	$(Q) $(MAKE) -C binfmt libbinfmt$(LIBEXT) EXTRAFLAGS="$(KDEFINE) $(EXTRAFLAGS)"
 
diff --git a/tools/Makefile.unix b/tools/Makefile.unix
index 52ccd3ca05..27444850bf 100644
--- a/tools/Makefile.unix
+++ b/tools/Makefile.unix
@@ -63,6 +63,13 @@ CONFIG_APPS_DIR = ../apps
 endif
 APPDIR := $(realpath ${shell if [ -r $(CONFIG_APPS_DIR)/Makefile ]; then echo "$(CONFIG_APPS_DIR)"; fi})
 
+# External code support
+# If external/ contains a Kconfig, we define the EXTERNALDIR variable to 'external'
+# so that main Kconfig can find it. Otherwise, we redirect it to a dummy Kconfig
+# This is due to kconfig inability to do conditional inclusion.
+
+EXTERNALDIR := $(shell if [ -r $(TOPDIR)/external/Kconfig ]; then echo 'external'; else echo '.external-dummy'; fi)
+
 # CONTEXTDIRS include directories that have special, one-time pre-build
 #   requirements.  Normally this includes things like auto-generation of
 #   configuration specific files or creation of configurable symbolic links
@@ -455,28 +462,28 @@ pass2dep: context tools/mkdeps$(HOSTEXEEXT) tools/cnvwindeps$(HOSTEXEEXT)
 # file in the NuttX tools GIT repository for additional information.
 
 config: apps_preconfig
-	$(Q) APPSDIR=${CONFIG_APPS_DIR} kconfig-conf Kconfig
+	$(Q) APPSDIR=${CONFIG_APPS_DIR} EXTERNALDIR=$(EXTERNALDIR) kconfig-conf Kconfig
 
 oldconfig: apps_preconfig
-	$(Q) APPSDIR=${CONFIG_APPS_DIR} kconfig-conf --oldconfig Kconfig
+	$(Q) APPSDIR=${CONFIG_APPS_DIR} EXTERNALDIR=$(EXTERNALDIR) kconfig-conf --oldconfig Kconfig
 
 olddefconfig: apps_preconfig
-	$(Q) APPSDIR=${CONFIG_APPS_DIR} kconfig-conf --olddefconfig Kconfig
+	$(Q) APPSDIR=${CONFIG_APPS_DIR} EXTERNALDIR=$(EXTERNALDIR) kconfig-conf --olddefconfig Kconfig
 
 menuconfig: apps_preconfig
-	$(Q) APPSDIR=${CONFIG_APPS_DIR} kconfig-mconf Kconfig
+	$(Q) APPSDIR=${CONFIG_APPS_DIR} EXTERNALDIR=$(EXTERNALDIR) kconfig-mconf Kconfig
 
 nconfig: apps_preconfig
-	$(Q) APPSDIR=${CONFIG_APPS_DIR} kconfig-nconf Kconfig
+	$(Q) APPSDIR=${CONFIG_APPS_DIR} EXTERNALDIR=$(EXTERNALDIR) kconfig-nconf Kconfig
 
 qconfig: apps_preconfig
-	$(Q) APPSDIR=${CONFIG_APPS_DIR} kconfig-qconf Kconfig
+	$(Q) APPSDIR=${CONFIG_APPS_DIR} EXTERNALDIR=$(EXTERNALDIR) kconfig-qconf Kconfig
 
 gconfig: apps_preconfig
-	$(Q) APPSDIR=${CONFIG_APPS_DIR} kconfig-gconf Kconfig
+	$(Q) APPSDIR=${CONFIG_APPS_DIR} EXTERNALDIR=$(EXTERNALDIR) kconfig-gconf Kconfig
 
 savedefconfig: apps_preconfig
-	$(Q) APPSDIR=${CONFIG_APPS_DIR} kconfig-conf --savedefconfig defconfig.tmp Kconfig
+	$(Q) APPSDIR=${CONFIG_APPS_DIR} EXTERNALDIR=$(EXTERNALDIR) kconfig-conf --savedefconfig defconfig.tmp Kconfig
 	$(Q) sed -i -e "/CONFIG_APPS_DIR=/d" defconfig.tmp
 	$(Q) grep "CONFIG_ARCH=" .config >> defconfig.tmp
 	$(Q) grep "^CONFIG_ARCH_CHIP_" .config >> defconfig.tmp; true
diff --git a/tools/Makefile.win b/tools/Makefile.win
index e6d793e914..bde2f73b07 100644
--- a/tools/Makefile.win
+++ b/tools/Makefile.win
@@ -48,6 +48,13 @@ CONFIG_APPS_DIR = ..\apps
 endif
 APPDIR := $(realpath ${shell if exist "$(CONFIG_APPS_DIR)\Makefile" echo $(CONFIG_APPS_DIR)})
 
+# External code support
+# If external/ contains a Kconfig, we define the EXTERNALDIR variable to 'external'
+# so that main Kconfig can find it. Otherwise, we redirect it to a dummy Kconfig
+# This is due to kconfig inability to do conditional inclusion.
+
+EXTERNALDIR := $(shell if [ -r $(TOPDIR)\external\Kconfig ]; then echo 'external'; else echo '.external-dummy'; fi)
+
 # CONTEXTDIRS include directories that have special, one-time pre-build
 #   requirements.  Normally this includes things like auto-generation of
 #   configuration specific files or creation of configurable symbolic links
@@ -411,22 +418,22 @@ pass2dep: context tools\mkdeps$(HOSTEXEEXT)
 # misc\tools\README.txt for additional information.
 
 config: apps_preconfig
-	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& kconfig-conf Kconfig
+	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& set EXTERNALDIR=$(EXTERNALDIR)& kconfig-conf Kconfig
 
 oldconfig: apps_preconfig
-	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& kconfig-conf --oldconfig Kconfig
+	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& set EXTERNALDIR=$(EXTERNALDIR)& kconfig-conf --oldconfig Kconfig
 
 olddefconfig: apps_preconfig
-	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& kconfig-conf --olddefconfig Kconfig
+	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& set EXTERNALDIR=$(EXTERNALDIR)& kconfig-conf --olddefconfig Kconfig
 
 menuconfig: configenv apps_preconfig
-	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& kconfig-mconf Kconfig
+	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& set EXTERNALDIR=$(EXTERNALDIR)& kconfig-mconf Kconfig
 
 nconfig: apps_preconfig
-	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& kconfig-nconf Kconfig
+	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& set EXTERNALDIR=$(EXTERNALDIR)& kconfig-nconf Kconfig
 
 savedefconfig: apps_preconfig
-	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& kconfig-conf --savedefconfig defconfig.tmp Kconfig
+	$(Q) set APPSDIR=$(patsubst "%",%,${CONFIG_APPS_DIR})& set EXTERNALDIR=$(EXTERNALDIR)& kconfig-conf --savedefconfig defconfig.tmp Kconfig
 	$(Q) sed -i -e "/CONFIG_APPS_DIR=/d" defconfig.tmp
 	$(Q) grep "CONFIG_ARCH=" .config >> defconfig.tmp
 	-$(Q) grep "^CONFIG_ARCH_CHIP_" .config >> defconfig.tmp
diff --git a/tools/ProtectedLibs.mk b/tools/ProtectedLibs.mk
index 306b53efe7..a978042059 100644
--- a/tools/ProtectedLibs.mk
+++ b/tools/ProtectedLibs.mk
@@ -48,6 +48,12 @@ USERLIBS =
 
 NUTTXLIBS += staging$(DELIM)libdrivers$(LIBEXT)
 
+# External code support
+
+ifeq ($(EXTERNALDIR),external)
+  NUTTXLIBS += staging$(DELIM)libexternal$(LIBEXT)
+endif
+
 # Add libraries for board support
 
 NUTTXLIBS += staging$(DELIM)libboards$(LIBEXT)