Solidity, Node Js, React Js, JavaScript,HTML,CSS,Bootstrap.
This project simulate system of stack to earn, you stack your nfts in the contract, and he gives benefices to you, on this case it give you back erc20 tokens as reward, when you unstack yours nfts automatically receive 1 token as reward.
Truffle, Metamask, IPFS, Ethers, Mocha.
He uses three kinds of contracts, each one does its job erc1155, erc721, erc20 all design patters from blockchain community openzzeplin.