Release Notes

0.4.1 Updates

Hedera Services Code (0.4.1)

  • Software update includes the ability for Hedera to dynamically set throttles on network transaction types.

  • The following throttles would be updated to: 1000 submit messages per second and 5 topic creates per second.

  • Reassigning of new Council Member nodes

Mirror Node (0.6.0)

This release was mainly focused on enhancing the stability and performance of the mirror node. We improved the transaction ingestion speed from 600 to about 4000 transactions per second. At the same time, we greatly improved the resiliency and performance of the GRPC module. We also added acceptance tests to test out HCS end to end.

Breaking Change

Please note that one potentially breaking change in this release is to reject subscriptions to topics that don't exist. This avoids the server having to poll repeatedly until it is created and taking up resources for a topic that may never exist. It is expected that clients or the SDK will poll periodically after creating a topic until that topic makes its way to the mirror node. This functionality is hidden behind a feature flag but will slowly be rolled out over the next month.

0.4.0 Updates

Note: Mainnet update is scheduled to occur on February 10, 2020.

Hedera Services Code (0.4.0)

  • Say hello to the Hedera Consensus Service! This release is the first to include HCS, allowing verifiable timestamping and ordering of application messages.

  • Network pricing has been updated to include HCS transactions and queries

  • Network throttle for HCS set to 1000 tps for submitting messages, and 100 tps for each of the other HCS operations.

  • Improved end to end testing.

  • General code clean up and refactoring.

  • ContractCall - TransactionReceipt response to ContractCall no longer includes the contractID called

  • CryptoUpdate - TransactionReceipt response to CryptoUpdate no longer includes the accountID updated

  • CryptoTransfer – CryptoTransfer transactions resulting in INSUFFICIENT_ACCOUNT_BALANCE error no longer list Transfers in the TransactionRecord transferList that were not applied

Mirror Node (0.5.3)

  • Now supports all HCS functionality including a streaming gRPC API for message topic subscription.

  • Changed how the mirror node verifies mainnet consensus. Mirror node now waits for at least third of node signatures rather than greater than two thirds to verify consensus.

  • Added new mainnet nodes to the mirror node address book.

  • Access still restricted to a white listed set of IP addresses. Request access here.

  • Please see the Mirror Node releases page for the full list of changes here.

  • We occasionally may encounter a situation where an additional 15-20 second delay in message round trip time is experienced and subscriber connections are dropped. No messages are lost, and the consensus time is not affected. Clients are encouraged to reconnect. This issue will be fixed in a subsequent release of the Hedera mirror node. Some third-party mirror nodes should not be affected by this issue. We also don't expect it to impact the exchanges using the REST end point for the mirror node.


  • Java SDK has been updated to support the Hedera Consensus Service

  • JavaScript/Typescript SDK has reached version 1.0.0, supporting all four mainnet services

  • JavaScript/Typescript SDK supports both running in the browser (with Envoy Proxy) and in Node.

  • Go SDK now supports all four mainnet services.


  • Transfer list within transaction records now shows only a single net amount in or out for each account, reflecting both transfers and any fees paid.

  • Fixed bug in fee schedule that had resulted in fees for ContractCallLocal, ContractGetBytecode, and getVersion queries being undercharged by ~33%

  • You may get more information regarding transaction record fees here.

SDK Extension Components

  • The Hedera SDK Extension Components (SXC) is an open sourced set of pre-built components that aim to provide additional functionality over and above HCS to make it easier and quicker to develop applications, particularly if they require secure communications between participants.

  • Components use the Hedera Java SDK to communicate with the Hedera Consensus Service.

  • Learn more about Hedera SXC here.