Arduino Library for STM32

Hello Folks,
as discussed via e-mail with Sir Kravets, I have a small question.

In the first step, I create myself a project with the following command:
tamhan@TAMHAN14:~/platformiohaus/demo1$ platformio init --board uno

Next, I would like to bring this to an STM microcontroller:
tamhan@TAMHAN14:~/platformiohaus/demo1$ platformio init --board nucleo_f401re

At this point, I need a working library which I was not able to find. Can anyone point me at a working version of the Arduino library for the STM32? I already tried changing the project definition:
platform = ststm32
board = nucleo_f401re
framework = arduino

But it did not work.

Well you / we have the problem that the used Arduino Core (GitHub - rogerclarkmelbourne/Arduino_STM32: Arduino STM32. Hardware files to support STM32 boards, on Arduino IDE 1.8.x including LeafLabs Maple and other generic STM32F103 boards) does indeed support STM32F4 (and F3) chips, but PIO doesn’t enable it for them except for STM32F1 boards (see PlatformIO Registry and put “STM32F4” in MCU field).

Available frameworks for boards are defined in .platformio\platforms\ststm32\boards. But I guess simple putting arduino in your board file there doesn’t solve the problem. Needs more changes to ststm32 and framework-arduinoststm32 use the that Arduino Core. You can work through the Custom Platform & Board — PlatformIO latest documentation documentation to learn about the structure, files and scripts to do that.