TinyMod has been updated again, but only slightly. It looks nearly the same. It behaves exactly the same. The changes are to make assembly easier and more robust. The diodes have been replaced with an MCP23017 i2c port expander. The microcontroller has been moved out from under the key switches, for easier assembly and repair. The switch footprints now only allow MX style switches and the switches fit better, requiring less solder. The firmware has been rewritten to accommodate the port expander. If I hadn't told you I'm not so sure you'd notice the difference.
Then we solder in the slider switch and the port expander from the back side. A rubber band holds the MCP23017 in place as we tack it at the corners.