Version 1 of the official open source Hedera SDKs for Java and Javascript was released on January 14th, 2020. On November 11th, 2020, the codebase for these open source SDKs was refactored to match that of the v2 Golang SDK, offering greater efficiencies and improved semantics for developing applications with Hedera Hashgraph.
With the release of v2 of the Java and Javascript SDKs, a majority of Hedera developer community members have migrated to v2. It has come time to begin the deprecation of v1 for Java and Javascript; the deprecation of v1 will be completed in October 2021, at which time Hedera will no longer support the inclusion of new Hedera API (HAPI) calls, capabilities, or hashgraph platform code.
Hedera will prioritize the inclusion of new capabilities and enhancements in v2 of the official SDKs between now and the time of complete deprecation in October 2021 of the v1 SDK, . If you’re still using v1 of the Hedera SDK, you will see a warning that deprecation is coming and you may not receive access to new capabilities and features as quickly as developers using v2.
It’s encouraged that all Hedera developers using v1 of the Java and Javascript libraries migrate to the latest version of v2 as soon as possible. For a complete list of changes between v1 and v2 and a migration reference guide, please refer to the following repositories: Java, JavaScript
Officially supported languages for Hedera SDKs are being considered but no concrete decisions have been made. If you’re interested in seeing a specific language officially supported, it’s highly recommended to create a Hedera Improvement Proposal (HIP) with as much detail as possible for both the community and Hedera Hashgraph, Inc. to review and comment. You can find the official HIP repository and instructions here: https://github.com/hashgraph/hedera-improvement-proposal
While Hedera officially supports open source SDKs in Java, Javascript, and Go, members of the Hedera developer community have created their own SDK for .NET. Although community SDKs are not maintained by Hedera, they offer an alternative for developers building Hedera applications and wanting to use other languages. The community SDKs Hedera is aware of can be found here: https://docs.hedera.com/hedera/sdks-and-apis/sdks