NeoLine ships first NEP-21 wallet integration for Neo N3

NeoLine has shipped v5.8.1 of its Chrome extension wallet with full support for NEP-21, the unified dAPI standard that Neo co-founder Erik Zhang finalized last week. The update makes NeoLine the first wallet in the Neo ecosystem to implement the standard’s IDapiProvider interface, a common set of methods that allows decentralized applications to communicate with wallet providers through a single, consistent integration.

NEP-21 addresses a longstanding fragmentation problem on Neo N3. Without a shared interface, dApp developers had to write separate integration logic for each wallet, and users encountered inconsistent behavior depending on which wallet they connected. The standard defines a transport-agnostic interface that works across browser extensions, desktop clients, and mobile wallets.

NeoLine implementation

With NeoLine’s implementation live, dApp developers building on Neo N3 can now write a single wallet integration using the NEP-21 interface and have it work out of the box. As other wallets adopt the standard, the same integration will extend to those providers without additional development work.

The update also introduces a standardized provider discovery mechanism. Wallets and dApps can now automatically locate each other in the browser via predefined window events, replacing the ad hoc detection methods dApp developers previously relied on. Standardized error codes provide developers with consistent, predictable error handling regardless of which compliant wallet a user connects with.

How it works

NeoLine’s v5.8.1 implementation covers the full NEP-21 specification. The wallet exposes methods spanning authentication, account management, contract invocation, transaction construction and signing, on-chain data queries, and event notifications.

Authentication follows the NEP-20 Challenge/Response protocol, the companion standard Zhang finalized earlier this month. NEP-20 defines an off-chain, address-based authentication scheme where users prove ownership of their Neo address through a cryptographic signature. NeoLine’s authenticate() method implements this flow natively.

The wallet reports its dAPI version as “1.0” and lists its standards compatibility, including NEP-11, NEP-17, and NEP-21.

The full developer documentation can be found at the link below:
https://tutorial.neoline.io/reference/neo3-provider-api