According to ChainCatcher news, the privacy coin project Zcash officially issued a statement stating that Zcash now has two independent sets of full node implementations that implement the same rules, namely Zebra and Zakura.
Zcash also raises the question of whether the second client actually changes the degree of decentralization of the network, or whether computing power remains the only critical factor. Zebra is a Rust full node implementation supported by the Zcash Foundation, and Zakura is another independent full node client.