diff --git a/boards/ESP8266.blocklist b/boards/ESP8266.blocklist
new file mode 100644
index 000000000..59268bfc6
--- /dev/null
+++ b/boards/ESP8266.blocklist
@@ -0,0 +1,3 @@
+[
+ {"class":"E","name":"FFT"}
+]
diff --git a/boards/ESP8266_BOARD.py b/boards/ESP8266_BOARD.py
index 8bf3ccec0..c3484eeaa 100644
--- a/boards/ESP8266_BOARD.py
+++ b/boards/ESP8266_BOARD.py
@@ -31,6 +31,7 @@
    ],
    'makefile' : [
      'DEFINES+=-DSAVE_ON_FLASH_MATH', 
+     'BLACKLIST=boards/ESP8266.blocklist', # force some stuff to be removed to save space
      'USE_DEBUGGER=0', # We can't use debugger as RTOS needs jsiIdle to keep exiting     
    ]
  }
diff --git a/src/jswrap_espruino.c b/src/jswrap_espruino.c
index 6e6fd9b3a..d4f1f0a8e 100644
--- a/src/jswrap_espruino.c
+++ b/src/jswrap_espruino.c
@@ -429,6 +429,8 @@ JsVarFloat jswrap_espruino_convolve(JsVar *arr1, JsVar *arr2, int offset) {
   return conv;
 }
 
+
+#ifndef ESP8266 // ESP8266 seems unable to leave this out of the firmware, even with gc-sections/flto!
 #if defined(SAVE_ON_FLASH_MATH) || defined(BANGLEJS)
 #define FFTDATATYPE double
 #else
@@ -608,6 +610,7 @@ void jswrap_espruino_FFT(JsVar *arrReal, JsVar *arrImag, bool inverse) {
     _jswrap_espruino_FFT_setData(arrImag, vImag, 0, pow2);
 }
 
+#endif //!ESP8266
 /*JSON{
   "type" : "staticmethod",
   "ifndef" : "SAVE_ON_FLASH",