Neo launches Message Bridge to enable cross-chain communication between Neo X and Neo N3

Neo has launched the Message Bridge on MainNet, introducing a new cross-chain communication layer between its EVM-compatible network Neo X and Neo N3. The infrastructure allows applications on either chain to exchange arbitrary data, trigger smart contract execution on the opposite network, and compose functionality across environments.

The Message Bridge expands Neo’s interoperability stack beyond asset transfers, which are already supported through the existing Token Bridge between Neo X and Neo N3. The development team indicated that reliability, monitoring, and security will remain ongoing priorities as usage grows.

Expanded cross-chain functionality

Unlike the Token Bridge, which is limited to moving assets, the Message Bridge supports arbitrary messages. These messages can execute contract logic on the destination chain, store data without execution, or return results back to the originating chain.

This design enables use cases such as accessing Neo N3’s native Oracles from Neo X, interacting with NeoFS from EVM-based applications, and building custom fungible or non-fungible token bridges. More complex cross-chain workflows, including asynchronous requests, swaps, and multi-step interactions, are also supported.

Neo X is developed by BaneLabs, a collaboration between Neo Global Development, Neo SPCC, and AxLabs. The teams have previously delivered infrastructure upgrades, including MEV resistance and the Token Bridge layer.

Architecture and security model

The Neo N3–Neo X bridge uses a three-layer smart contract architecture deployed on each chain. This includes bridge management contracts for governance and role-based access control, a message bridge contract that handles cross-chain communication, and native or token bridge contracts for asset transfers.

Cross-chain operations are validated through a multi-signature validator model. A configurable threshold of validators must approve withdrawal roots before execution, with separate cryptographic key types used on Neo N3 and EVM chains. The system tracks deposits and withdrawals using rolling Merkle roots, reducing gas costs by batching operations.

Security features include strict role separation, granular pause controls, and execution time windows for messages.

Typescript SDK

Alongside the MainNet deployment, BaneLabs has released several open-source repositories to support integration. These include smart contracts for both EVM and Neo environments, a TypeScript SDK for frontend and backend applications, and example projects demonstrating message execution and result handling across chains.

The SDK abstracts Neo N3’s stack-based contract calls and manages encoding differences between the two environments, lowering the barrier for EVM developers to build cross-chain applications

The full announcement can be found at the link below:
https://neo.org/blog/details/4329