Build esp32 failed: App is too big


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My goal is: trying to build new firmware after update mos version release

but the result I see is: build esp32 failed: App is too big

after that, i already check with

mos update latest

have same error.


try mos build --clean

If that doesn’t work try to delete the build/ and deps/ directories, then build again


SAD :(.
Still got that error even use mos build --clean

or delete build/


just come back to version 2.17.0 and they would be fine


“app is too big” means that you are uploading a bigger chunk than you are allowed to. That means that your source directory is too big. That means that you did not erase de deps directory (you just deleted the build directory…)


with mos 2.18.0, when i build succesfully an firmware for ESP8266, but that chip going to CORE_DUMP…

and with 2.17.0, i can build successfully both ESP32 and ESP8266 without CORE_DUMP or any error


How exactly do you downgrade mos version?


You don’t need to downgrade the mos tool. Just modify these lines

libs_version: ${mos.version}
modules_version: ${mos.version}
mongoose_os_version: ${mos.version}

with the version of your choice, e.g. 2.17.0.