To compile this project you need MSYS2, which can be downloaded here: https://www.msys2.org/
After installing MSYS2 you need to run the following command
make install-arduino-cli
to install Arduino CLI.
make install-arduino-cli
- installs Arduino CLI in ./bin/ directory
make install-deps
- installs libraries and boards
make build
- compiles the project
make flash
- compiles and flashes the project into ESP8266 connected on port COM3