I saw from a 5 year old post that most users have switched to platformIO. Since that time and particularly in the last 6 months Arduino has finally got their 2.x platform running nicely on windoz, mac and linux.
By just selecting the board the whole environment updates to the latest stuff the board vendor has put in their .json file.
I currently use Arduino uno, mini, due, but mostly Teensy 3.2, 4.0, 4.1 and ESP8266 all with a simple switch. Currently the links to your latest firmware, version 8.2.3 won't compile because your using outdated tool chain for Arduino uno. If you had the json file configured for your version you could continue to use it and be transparent to the user who selects the openEVSE board json.
It would be really nice if you could look into updating to this.
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