Distributed Ledger Technologies (DLTs) commonly have simple and inflexible forms of immutability. Hedera supports a more flexible form of controlled mutability, which allows certain changes under certain circumstances, but prevents other types of changes. One area where this is particularly important is for smart contracts.
We’re still so early in this journey we call Hedera Hashgraph. We just started opening up testnets to a wider audience of developers and boy did we learn some really cool things…things that have informed how we want to build our SDKs. Frankly, we need to make sure that developers absolutely love the SDK experience. So we’re getting smart and fun about building our SDKs with the help of those very same developers.
Some consensus algorithms are fragile — they cannot adapt to changes, either in the membership of nodes, or in the influence of those nodes towards consensus. The result is that such changes cause consensus to be prevented or corrupted. This can be a problem for some types of distributed ledgers, but it is not a problem for Hedera.