NEM was written in Java, and a C++ version is in progress. The NEM blockchain uses an original consensus mechanism called Proof of Importance. XEM cannot be mined. The total finite sum of 8,999,999,999 XEM was distributed to stakeholders upon project launch. XEM are either bought, or earned as a reward for 'harvesting', i.e. processing transactions Unlike other blockchains and institutions, the NEM blockchain does not instrinsically support smart contract.