Gasless Transactions

Another major innovation brought by the RAILGUN system is the ability to send transactions without needing to spend the underlying blockchain’s gas currency. Through the power of Relayers and complex ZK circuits, users can interact with RAILGUN entirely in their currency of choice. For example, a user would not need to hold a small balance of ETH to pay for transactions on the Ethereum network and could instead choose to only hold and spend a stablecoin like DAI with all associated fees being paid in DAI.
This is achieved through something called a “Meta Transaction”, a special form of Ethereum/blockchain transaction that is nested within another transaction. The gas fee can be paid in whatever asset the user specifies with the Relayer and nested transaction performing any conversion frictionlessly for the user. Like any other spend transactions, a Meta Transaction in RAILGUN calls the transact() function.