diff --git a/platformio.ini b/platformio.ini
index a8940879e..4ee70850f 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -25,7 +25,7 @@ default_envs = linux # nrf52840dk-geeksville # linux # or if you'd like to chang
 
 ; note: we add src to our include search path so that lmic_project_config can override
 ; FIXME: fix lib/BluetoothOTA dependency back on src/ so we can remove -Isrc
-build_flags = -Wno-missing-field-initializers -Isrc -Isrc/mesh -Isrc/gps -Ilib/nanopb/include -Os -Wl,-Map,.pio/build/output.map 
+build_flags = -Wno-missing-field-initializers -Isrc -Isrc/mesh -Isrc/gps -Ilib/nanopb/include -Wl,-Map,.pio/build/output.map 
   -DHW_VERSION_${sysenv.COUNTRY}
   -DAPP_VERSION=${sysenv.APP_VERSION}
   -DHW_VERSION=${sysenv.HW_VERSION}
@@ -64,7 +64,7 @@ lib_deps =
   Wire ; explicitly needed here because the AXP202 library forgets to add it
   SPI
   
-; Common settings for Ardino targets
+; Common settings for conventional (non Portduino) Ardino targets
 [arduino_base]
 
 framework = arduino
@@ -72,6 +72,8 @@ framework = arduino
 lib_deps =
   ${env.lib_deps}
 
+build_flags = ${env.build_flags} -Os
+
 ; Common settings for ESP targes, mixin with extends = esp32_base
 [esp32_base]
 extends = arduino_base
@@ -81,7 +83,7 @@ src_filter =
 upload_speed = 921600
 debug_init_break = tbreak setup
 build_flags =
-  ${env.build_flags} -Wall -Wextra -Isrc/esp32 -Isrc/esp32-mfix-esp32-psram-cache-issue -lnimble -std=c++11 
+  ${arduino_base.build_flags} -Wall -Wextra -Isrc/esp32 -Isrc/esp32-mfix-esp32-psram-cache-issue -lnimble -std=c++11 
   -DLOG_LOCAL_LEVEL=ESP_LOG_DEBUG -DCORE_DEBUG_LEVEL=ARDUHAL_LOG_LEVEL_DEBUG
   -DAXP_DEBUG_PORT=Serial
 # Hmm - this doesn't work yet
@@ -149,7 +151,7 @@ build_flags =
 platform = https://github.com/HelTecAutomation/platform-asrmicro650x.git ; we use top-of-tree because stable version has too many bugs - asrmicro650x
 board = cubecell_board_plus
 ; FIXME, bug in cubecell arduino - they are supposed to set ARDUINO
-build_flags = ${env.build_flags} -DARDUINO=100 -Isrc/cubecell
+build_flags = ${arduino_base.build_flags} -DARDUINO=100 -Isrc/cubecell
 src_filter = 
   ${env.src_filter} -<esp32/> -<nrf52/>
   
@@ -163,7 +165,7 @@ debug_tool = jlink
 build_type = debug ; I'm debugging with ICE a lot now
 ; note: liboberon provides the AES256 implementation for NRF52 (though not using the hardware acceleration of the NRF52840 - FIXME)
 build_flags = 
-  ${env.build_flags} -Wno-unused-variable 
+  ${arduino_base.build_flags} -Wno-unused-variable 
   -Isrc/nrf52 
   -Isdk-nrfxlib/crypto/nrf_oberon/include -Lsdk-nrfxlib/crypto/nrf_oberon/lib/cortex-m4/hard-float/ -lliboberon_3.0.3 
 ;-DCFG_DEBUG=3
@@ -249,6 +251,6 @@ lib_deps =
 [env:linux]
 platform = https://github.com/geeksville/platform-portduino.git
 src_filter = ${env.src_filter} -<esp32/> -<nimble/> -<nrf52/>
-build_flags = ${env.build_flags} 
+build_flags = ${arduino_base.build_flags} 
 framework = arduino
 board = linux_x86_64