diff --git a/esp32/BUILD b/esp32/BUILD
index 9a3862f..f3ab38a 100644
--- a/esp32/BUILD
+++ b/esp32/BUILD
@@ -105,11 +105,11 @@ Default('esp32')
 
 # Automate building / flashing.
 BOARDS = {
-  'esp32': '--fqbn=esp32:esp32:esp32:PSRAM=disabled,PartitionScheme=no_ota,CPUFreq=240,FlashMode=qio,FlashFreq=80,FlashSize=4M,UploadSpeed=921600,LoopCore=1,EventsCore=1,DebugLevel=none,EraseFlash=none',
-  'esp32s2': '--fqbn=esp32:esp32:esp32s2:CDCOnBoot=default,MSCOnBoot=default,DFUOnBoot=default,UploadMode=default,PSRAM=disabled,PartitionScheme=default,CPUFreq=240,FlashMode=qio,FlashFreq=80,FlashSize=4M,UploadSpeed=921600,DebugLevel=none,EraseFlash=none',
-  'esp32s3': '--fqbn=esp32:esp32:esp32s3:PSRAM=disabled,FlashMode=qio,FlashSize=4M,LoopCore=1,EventsCore=1,USBMode=hwcdc,CDCOnBoot=default,MSCOnBoot=default,DFUOnBoot=default,UploadMode=default,PartitionScheme=default,CPUFreq=240,UploadSpeed=921600,DebugLevel=none,EraseFlash=none',
-  'esp32c3': '--fqbn=esp32:esp32:esp32c3:CDCOnBoot=default,PartitionScheme=default,CPUFreq=160,FlashMode=qio,FlashFreq=80,FlashSize=4M,UploadSpeed=921600,DebugLevel=none,EraseFlash=none',
-  'esp32cam': '--fqbn=esp32:esp32:esp32cam:CPUFreq=240,FlashMode=qio,PartitionScheme=huge_app,FlashFreq=80,DebugLevel=none,EraseFlash=none',
+  'esp32': '--fqbn=esp32:esp32:esp32:PSRAM=disabled,PartitionScheme=no_ota,CPUFreq=240,FlashMode=qio,FlashFreq=80,FlashSize=4M,UploadSpeed=921600,LoopCore=1,EventsCore=1,EraseFlash=none',
+  'esp32s2': '--fqbn=esp32:esp32:esp32s2:CDCOnBoot=default,MSCOnBoot=default,DFUOnBoot=default,UploadMode=default,PSRAM=disabled,PartitionScheme=default,CPUFreq=240,FlashMode=qio,FlashFreq=80,FlashSize=4M,UploadSpeed=921600,EraseFlash=none',
+  'esp32s3': '--fqbn=esp32:esp32:esp32s3:PSRAM=disabled,FlashMode=qio,FlashSize=4M,LoopCore=1,EventsCore=1,USBMode=hwcdc,CDCOnBoot=default,MSCOnBoot=default,DFUOnBoot=default,UploadMode=default,PartitionScheme=default,CPUFreq=240,UploadSpeed=921600,EraseFlash=none',
+  'esp32c3': '--fqbn=esp32:esp32:esp32c3:CDCOnBoot=default,PartitionScheme=default,CPUFreq=160,FlashMode=qio,FlashFreq=80,FlashSize=4M,UploadSpeed=921600,EraseFlash=none',
+  'esp32cam': '--fqbn=esp32:esp32:esp32cam:CPUFreq=240,FlashMode=qio,PartitionScheme=huge_app,FlashFreq=80,EraseFlash=none',
   'tdongles3': '--fqbn=esp32:esp32:esp32s3:CDCOnBoot=cdc,FlashSize=16M,PartitionScheme=huge_app',
 }
 for board_base in BOARDS:
@@ -119,6 +119,7 @@ for board_base in BOARDS:
     if optional:
       options = options.replace('PartitionScheme=default', 'PartitionScheme=huge_app')
       options = options.replace('PartitionScheme=no_ota', 'PartitionScheme=huge_app')
+    options += ',DebugLevel=$${DEBUG_LEVEL:-none}'
     board = board_base + optional
     clobber = f'rm -rf {WINTMP}/ueforth_esp32/{board}_dir/ && '
     setup = (f'mkdir -p {WINTMP}/ueforth_esp32/{board}_dir/build && '