The Arduino IDE has an option to program with a programmer instead of via the serial port.
I have several programmers that should work with the attiny85; IE: AVR ISPII, Atmel ICE, PicKit-4, AdaFruit USB mini-ISP, and an AVR-Dragon.
What I will have to do is plug the chip into a breadboard to power it and make connections to the programmer.
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If I have the hex file I can probably also use MPLAB IPE with either the Atmel ICE or the PicKit4 to program it, or use AVR-DUDE from the command line.
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