Skip to main content

What CoRelayer does

On MultiversX, every transaction costs a fee, and that fee is paid in EGLD. This is a small thing until it is the only thing standing between you and a transaction: you hold USDC, you want to send USDC, and you cannot, because you do not have the network's own token.

CoRelayer removes that requirement. A relayer — a wallet we operate — pays the fee for your transaction. You still sign it, it is still your transaction, it still moves only what you told it to move. What changes is who is charged for the network fee.

Who pays what​

PaysIn
You, or the app you use if it pays for its usersthe planUSDC, per 30 days, on chain
CoRelayerthe network fee of every transaction we relayEGLD, from the relayer wallet
The networknothing — it collects the fee from the relayer

There is no allowance to grant, no token to approve and no custody step. The only thing you hand over is a transaction you signed yourself.

If you build an app, your plan can pay for your users as well. From Builder up, one sponsor key on your server pays for the transactions of every user whose key your server holds or reaches (embedded or custodial wallets, game servers, agent fleets), with no list of wallets to keep; the plan limits transactions, not users. It pays for calls to the contracts you list, not for payments to arbitrary addresses. (Pay for your users)

The sixty-second mental model​

  1. You buy a plan. A plan is a number of Relay Units per month, paid for in USDC by a transaction to the CoRelayer contract. The contract turns your USDC into credits and into a plan block that records exactly what you bought.
  2. You ask for a relayer. Because MultiversX is sharded, the relayer has to be in the same shard as you. CoRelayer picks one and hands you its address plus a short-lived lease — a token that says "this relayer will co-sign for you for the next sixty seconds".
  3. You sign once. The relayer address is one of the fields your signature covers, so it cannot be swapped afterwards. There is no second variant and no second signature. (Why one signature)
  4. We co-sign and broadcast. The relayer adds its own signature over the same bytes and the transaction goes to the network.
  5. We count it. The transaction's worst-case fee is converted into Relay Units and taken off your plan.

What this is good for​

  • Wallets and apps that do not want a new user's first experience to be "go and buy EGLD somewhere else first". One plan and one sponsor key pay for every user whose key your server holds or reaches (embedded or custodial wallets, game servers, agent fleets), for calls to the contracts you list; the plan limits transactions, not users. A wallet whose users pay each other sends to people's addresses, which a sponsor key can't cover: send those payments from wallets you name, or let each user hold a plan of their own. (Paying for other senders)
  • Businesses that pay in a stable unit. A plan costs a known number of USDC per month; the EGLD price moves against us, not against you, for the period you paid for.
  • Programs and agents that need to transact without a human topping up a gas balance. An agent can discover the price, buy a plan or pay per request, and relay — without a person in the loop. (For agents)

What this is not​

  • It is not custody. We never hold your tokens and we cannot move them.
  • It is not a wallet. You bring your own keys; we never see a private key of yours.
  • It is not a way to send a transaction you could not otherwise send. Every rule of the protocol still applies: your nonce, your balance, the contract you call.
  • It is not free. The relayer spends real EGLD on your behalf, which is what the subscription pays for.

The honest limits​

  • A relayer can be slow or decline. That is the real risk of this design, and it is why the relayer is named to you before you sign and why you can check its state on chain yourself. (Security)
  • A transaction whose worst case is large costs more than one Relay Unit. The unit is defined so that an ordinary transfer or contract call is exactly one. (Relay Units)
  • Service measurements appear on this site only once there are measurements to show. (Status and SLOs)

Next​

On this page