Individuals are the ultimate nullifiers.
Legislation can set the stage to nullify federal acts by withdrawing cooperation and removing a lawyer of laws, but ultimately nullification is most effective when individuals are willing to do the things governments prohibit.
The lack of regulation when state and local police stand down creates space for markets to grow, even when the minimal threat of federal enforcement remains. This is exactly what happened after Maine legalized marijuana through a voter referendum.
The ballot initiative passed in November 2016 legalized marijuana. Sort of.
The referendum made it legal for adults in Maine to grow up to six mature marijuana plants and possess up to 2½ ounces of marijuana for personal use. But for more than a year,  they couldn’t legally buy or sell cannabis. The referendum left it to the state government to create a framework for licensing sellers and commercial cultivation. That didn’t happen until May 2017 after the legislature overrode a Gov. Paul LePage veto of a bill to implement and regulate the state’s adult-use marijuana market. Up until that point, it was still illegal to buy or sell cannabis in the state.
Read the rest at tenthamendmentcenter.com.