COZ has released a new milestone update for the Neo3 version of Neon.js, its JavaScript SDK for Neo. The new version, v5.0.0-next5, brings with it Preview4 compatibility and full support for both the neon-core and neon-api packages. 

Developers will be able to deploy smart contracts or interact with them through real or test invocations in the version. VM operation prices have also been adjusted in line with the new dynamic and adjustable model in the core.

NEP-17 support is another notable addition, introducing new functionality to enable contracts to respond when receiving contracts.

Neon.js also now offers NetworkFacade, a new high level API class that simplifies wallet interactions such as fetching token balances or creating new transactions. Neon.js users from Neo2 will also notice the deprecation of Fixed8, replaced with BigInteger.

A full overview of the latest changes and other improvements introduced in previous versions of the Neo3 SDK can be found at the link below:
https://github.com/CityOfZion/neon-js/blob/next/docs/changelog/latest.md