NAC Usage

EVM to Michelson

Cross-interface calls go through the gateway contract of the caller's interface. This page describes how to initiate a cross-interface call from the EVM interface.

The EVM-to-Michelson gateway is a precompile deployed at:

0xff00000000000000000000000000000000000007

callMichelson

Call a Michelson contract by providing:

Parameter	Type	Description
destination	string	The Michelson contract address (KT1… base58check)
entrypoint	string	The target entrypoint name
data	bytes	Michelson-encoded parameters

A Michelson KT1… address is 22 bytes in base58check form and does not fit into a 20-byte EVM address type. The gateway therefore takes the destination as a string and parses it on the Michelson side.

interface INativeAtomicGateway {
    function callMichelson(
        string calldata destination,
        string calldata entrypoint,
        bytes calldata data
    ) external payable;
}

INativeAtomicGateway gateway = INativeAtomicGateway(
    0xff00000000000000000000000000000000000007
);
gateway.callMichelson("KT1…", "default", michelsonParams);

The data parameter must be encoded in Michelson binary format. On-chain encoding libraries are available to help construct these payloads from within Solidity contracts.

FA1.2 wrapper

For calling FA1.2 token contracts specifically, a convenience precompile is available at:

0xff00000000000000000000000000000000ffff09

This precompile provides approve and transfer methods that handle Michelson parameter encoding automatically, without requiring manual binary encoding.

Return value

In the case of a regular Michelson call, there is no return value.

In case of a call to a Michelson view, the Michelson return value is ABI-encoded as bytes and returned to the calling Solidity contract.

For non-effectful calls (read-only views), use the call_view entry point on the Michelson gateway.

On-chain libraries for encoding and decoding across runtimes are provided to simplify this.