Degrowth advocates promote the use of regional and complementary currencies to localize economies and make the system more ecologically sustainable.

The best solution for a demurrage implementation is to use bitcoin as the base layer currency and have complementary currencies to bitcoin, which local communities can control and operate. One way this can happen is to create stablecoins on the lightning network.

I think as lightning matures, we will see complementary currencies develop on bitcoin that will challenge the status quo of our dominant fiat currencies and democratize control of money creation. From the Nashian perspective, participants in these regional currencies could measure the quality of their currency against the bitcoin standard, and demand better from local governments. For those who value the strength of the 21-million bitcoin cap, there is no harm done to the main protocol.

Not all communities will operate on complementary currencies, some will decide to operate using bitcoin and bitcoin alone.