Flashing an ATtiny85 with a NodeMCU? I recently purchased a Digispark for some of my smaller electronics projects. After it initially being a great little board, I soon found myself unable to flash the board in the same way I had done before i.e. according to the method described here. I am still unsure as to why the previous flashing method stopped working but have been unable to overcome the issue, nor have I found many other accounts of similar problems online.

After a period of frustration, unable to even find a way to reset the board, it dawned upon me that I may be able to use an Arduino to flash the board as seen here. However, the issue is that all the tutorials I could find online assumed that an Arduino Uno could be easily accessed, which is not the case for me. Despite this, I do have a few NodeMCUs hanging around and would love it if I could use them to flash the Digispark. 

My question is: how exactly would I flash the Digispark using a NodeMCU (if it is even possible)?

P.S. Whilst I am aware that the Digispark board has a number of other components aside from the ATtiny85 chip, the pinouts (not the USB) of the board allow for direct interfacing with the chip.

Thank you in advance for any help,

Kind regards,
Rocco
It can be done. Your Digispark has SPI pins, which are ISP pins. For the esp8266 there is an ESP8266AVRISP library for OTA upload to AVR. You can use the example of the library.

You must wire the SPI pins and ground together. Wire reset pin of Digispark to io 5 (D1) of NodeMcu. You should use level conversion, but esp8266 tolerates 5 V TTL (not recommended for long term). Do not wire the SS pin.