ESP8266 Community Forum

With some of the pins you could scrape some of the solder mask off to give you a larger area to work with. You could also solder to the chip side of the resistors?

The serial pins are the last 2 pins on the right-side of the top row in the close-up photo. Unless there's something I don't understand, those are the pins I need to make a connection to, and they have absolutely no traces leading to them. I have to solder directly to the chip leads - there is nothing else.

Otherwise if this thing has the right version of sonoff firmware, then I can use something like sonata to flash it OTA. But this thing must be a Sonoff clone, so there's no telling if Sonata would work. But I will at some point soon try it.

I think trying the Sonoff flash OTA approach is worth a go.

The other approach would be painful - you might be able to build some sort of contact jig that fits over the top and makes contact with the serial pins. I've done this before by spraying the unit very lightly with oil and then covering it in white glue to make a plastic mold - once it's set, you then push wires through at the pins

Don't forget what I said earlier. You also need to toggle RST (although that might be done by power cycling) and GPIO 0!