AxLabs has unveiled the latest version of neow3j, specifically version 3.24.1, which delivers comprehensive compatibility with Neo 3.9. This update enhances the development toolkit with notable improvements to storage APIs and broadens support for Neo Enhancement Proposals (NEPs).
Originally launched in 2018, neow3j serves as a robust toolkit for developers working with the Neo blockchain, offering high-level APIs for wallet management, smart contract interactions, and blockchain queries. The toolkit includes a development package (devpack) that allows for writing Neo smart contracts directly in Java, complete with compiler support for generating bytecode for the Neo Virtual Machine.
Released on February 12, the neow3j 3.24.1 update ensures seamless integration with Neo-CLI v3.9.1, allowing developers to utilize the latest features of the blockchain. These features include the contract fee whitelist, the Treasury native contract, and improved precision in execution fees, which were introduced in the January 2026 Neo v3.9 update.
Key Enhancements in Neo 3.9 Support
This release adds extensive support for features introduced in Neo 3.9 across both the SDK and devpack. The enhancements to the PolicyContract aspect of the SDK are particularly significant, as they now expose all Neo 3.9 PolicyContract methods. This includes the ability to retrieve blocked accounts and recover assets from long-term blocked accounts, along with complete management of whitelist fee contracts.
Additionally, the execution fee factor now supports four extra decimal places of precision. The new getExecPicoFeeFactor method provides full precision values, while the existing method maintains backward compatibility.
Modernization of Storage APIs
The update also modernizes storage APIs by moving away from context-based storage access. The new storage methods operate directly on a contract”s storage, simplifying the coding process and minimizing potential misuse. This includes the introduction of four new system calls that allow for contract-bound storage access without the need for context management.
Furthermore, the StorageMap class has been simplified, allowing developers to create storage maps more easily. All storage methods now support a comprehensive range of key and value types.
Expansion of NEP Standards
The devpack now includes support for three new NEPs: NEP-24, which standardizes royalty payment information for NFT contracts; NEP-26, formalizing callback methods for NEP-11 token transfers; and NEP-27, which provides standards for handling NEP-17 fungible token transfers.
In addition to these updates, the native StdLib contract interface has been enhanced with new methods for hex string conversion, facilitating more straightforward implementation within smart contracts.
As part of the update, there is a deprecation notice for the StorageContext class and all context-requiring storage methods, which are slated for removal in a future version. Developers are urged to transition to the new context-free storage APIs.
This latest release marks a significant step forward for neow3j, enhancing developer capabilities while ensuring compatibility with the evolving Neo ecosystem. The full release can be accessed through the neow3j GitHub page.
