I go in the opposite direction. I made a hot water bath from a styrofoam "cooler" and an aquarium heater. I heat up about two liters of water in the MW then put it in the "cooler" with the aquarium heater and the glass jug of developer. Wait a bit and the developer warms up to 100-110 degrees F. The only hassle is pouring the developer in and out of the developer tray. We must suffer for art.....

The simple styrofoam cooler. It keeps hot stuff hot. It keeps cold stuff cold. How does it know?