Tendermint Core v0.34 has been released
Late last year, we quietly released the new version of Tendermint Core which will support the Cosmos Stargate upgrade, v0.34.0. Today we are releasing v0.34.1, which includes bug fixes and other small improvements for the 0.34 release series. This blog post serves as a quick recap of the major features included in this release series, but for a full list of changes, please refer to the changelog, and for detailed notes on breaking changes, see the Upgrading Instructions.
What’s new in Tendermint Core v0.34
Protocol Buffers
Like other Stargate-compatible Cosmos projects, Tendermint Core adopts Protocol Buffers, which has led to big improvements in performance and developer experience. I’ve written before about the implications of Protocol Buffers, and what this means for application developers:
State sync
Tendermint Core v0.34.0 introduces a new feature called “state sync,” which allows nodes to join preexisting networks by syncing application state rather than by replaying the full block history. Without state sync, it can take a new node days to catch up; but with state sync, it only takes a few minutes!
To learn more about how to use state sync in your applications, please see Erik Grinaker’s post, “Tendermint Core State Sync for Developers.”
Light client
We’ve rewritten the Tendermint Core light client to be weakly subjective, which — despite the name — means that it’s more strongly secure. This is critical for IBC security, since IBC uses the Tendermint Core light client to verify that packets have been included on both sides of an IBC transaction.
For those curious about the implementation details of the new light client, Anton Kaliaev has written an overview of its goals and design:
Evidence handling
The introduction of a new light client means the introduction of a new attack surface for Byzantine behavior. Consequently, we’ve completely revisited the way that Tendermint Core handles evidence of misbehavior, and we’ve given the light client ways to identify malicious behavior and to report it back to full nodes, who can then come to consensus on this evidence and hold any misbehaving parties accountable.
These are some of the major new features introduced in Tendermint Core v0.34, but there are also more than one hundred bug fixes, performance improvements, optimizations, simplifications, refactors and user experience improvements. To see them all, please check out the changelog.
