diff --git a/ueforth/Makefile b/ueforth/Makefile
index 7349bff..dffadff 100644
--- a/ueforth/Makefile
+++ b/ueforth/Makefile
@@ -128,7 +128,7 @@ $(GEN)/windows_boot.h: common/source_to_string.js $(WINDOWS_BOOT) | $(GEN)
 
 ARDUINO_BOOT = common/boot.fs common/vocabulary.fs \
                arduino/arduino.fs arduino/arduino_highlevel.fs \
-               arduino/hide_io.fs common/highlevel.fs \
+               arduino/bindings.fs common/highlevel.fs \
                common/filetools.fs common/utils.fs \
                common/tasks.fs common/streams.fs arduino/arduino_server.fs \
                arduino/esp_camera.fs common/blocks.fs \
diff --git a/ueforth/arduino/arduino.fs b/ueforth/arduino/arduino.fs
index ba89dc7..5b78bc4 100644
--- a/ueforth/arduino/arduino.fs
+++ b/ueforth/arduino/arduino.fs
@@ -24,12 +24,6 @@ forth definitions
 2 constant OUTPUT
 2 constant LED
 
-( WiFi Modes )
-0 constant WIFI_MODE_NULL
-1 constant WIFI_MODE_STA
-2 constant WIFI_MODE_AP
-3 constant WIFI_MODE_APSTA
-
 ( Startup Setup )
 -1 echo !
 115200 Serial.begin
diff --git a/ueforth/arduino/arduino.template.ino b/ueforth/arduino/arduino.template.ino
index 24ca27b..8e058db 100644
--- a/ueforth/arduino/arduino.template.ino
+++ b/ueforth/arduino/arduino.template.ino
@@ -42,10 +42,14 @@
 #define PUSH(v) (DUP, tos = (cell_t) (v))
 
 #define PLATFORM_OPCODE_LIST \
-  /* Allocation and Strings */ \
+  /* Memory Allocation */ \
   X("MALLOC", MALLOC, tos = (cell_t) malloc(tos)) \
   X("SYSFREE", FREE, free((void *) tos); DROP) \
   X("REALLOC", REALLOC, tos = (cell_t) realloc((void *) *sp, tos); --sp) \
+  X("heap_caps_malloc", HEAP_CAPS_MALLOC, tos = (cell_t) heap_caps_malloc(*sp, tos); --sp) \
+  X("heap_caps_free", HEAP_CAPS_FREE, heap_caps_free((void *) tos); DROP) \
+  X("heap_caps_realloc", HEAP_CAPS_REALLOC, \
+      tos = (cell_t) heap_caps_realloc((void *) sp[-1], *sp, tos); sp -= 2) \
   /* Serial */ \
   X("Serial.begin", SERIAL_BEGIN, Serial.begin(tos); DROP) \
   X("Serial.end", SERIAL_END, Serial.end()) \
diff --git a/ueforth/arduino/arduino_server.fs b/ueforth/arduino/arduino_server.fs
index 00ce52f..4452c99 100644
--- a/ueforth/arduino/arduino_server.fs
+++ b/ueforth/arduino/arduino_server.fs
@@ -102,7 +102,7 @@ window.onload = function() {
 variable webserver
 20000 constant out-size
 200 stream input-stream
-out-size dup stream output-stream
+out-size stream output-stream
 create out-string out-size 1+ allot align
 
 : handle-index
diff --git a/ueforth/arduino/hide_io.fs b/ueforth/arduino/bindings.fs
similarity index 76%
rename from ueforth/arduino/hide_io.fs
rename to ueforth/arduino/bindings.fs
index a964df8..359f6de 100644
--- a/ueforth/arduino/hide_io.fs
+++ b/ueforth/arduino/bindings.fs
@@ -1,4 +1,5 @@
-( Migrate various words to separate vocabularies )
+( Migrate various words to separate vocabularies, and constants )
+
 vocabulary Wire   Wire definitions
 transfer{
   Wire.begin Wire.setClock Wire.getClock
@@ -25,6 +26,7 @@ transfer{
 forth definitions
 
 vocabulary WiFi   WiFi definitions
+
 transfer{
   WiFi.config
   WiFi.begin WiFi.disconnect
@@ -32,8 +34,14 @@ transfer{
   WiFi.macAddress WiFi.localIP
   WiFi.mode
   WiFi.setTxPower WiFi.getTxPower
-  WIFI_MODE_APSTA WIFI_MODE_AP WIFI_MODE_STA WIFI_MODE_NULL
 }transfer
+
+( WiFi Modes )
+0 constant WIFI_MODE_NULL
+1 constant WIFI_MODE_STA
+2 constant WIFI_MODE_AP
+3 constant WIFI_MODE_APSTA
+
 forth definitions
 
 vocabulary SD_MMC   SD_MMC definitions
@@ -92,6 +100,21 @@ forth definitions
 internals definitions
 transfer{
   malloc sysfree realloc
+  heap_caps_malloc heap_caps_free heap_caps_realloc
 }transfer
+
+( Heap Capabilities )
+binary
+0001 constant MALLOC_CAP_EXEC
+0010 constant MALLOC_CAP_32BIT
+0100 constant MALLOC_CAP_8BIT
+1000 constant MALLOC_CAP_DMA
+: MALLOC_CAP_PID ( n -- ) 10000 over 11 ( 3 ) - for 2* next ;
+000010000000000 constant MALLOC_CAP_SPIRAM
+000100000000000 constant MALLOC_CAP_INTERNAL
+001000000000000 constant MALLOC_CAP_DEFAULT
+010000000000000 constant MALLOC_CAP_IRAM_8BIT
+010000000000000 constant MALLOC_CAP_RETENTION
+decimal
 forth definitions