Hello everyone. I'm "playing" with gateway API and have a question. I heard, that Elrond doesn't save blocks forever (as bitcoin, eth, etc...) in the chain. Can I be sure, that my block with the transaction will be always in chain + accessible by its nonce/hash (and transactions too)? Are there any corner cases in saving blocks with transactions and transactions itself?

Hi there @T_trojan! All transactions that have been included into a block which have been finalized into one of the shards will always be available inside that shard's state / history. There are few entities that participate into the elrond network: 1. Validator nodes 2. Observer nodes 1. The validator nodes are required to keep only the last few epochs in order to provide data availability for the new validators coming and making sure that new blocks are being produced. 2. Observers can be of two types: 2.1 Live data - Where only the current state in synced including the transactions from the current epoch and all upfront ones (especially used for VM Queries or so called SC View functions) 2.2. Full history- Where the state will be synced and maintained from genesis up to the current block height, therefore making the entire chain history available for everyone on their own setup.

Blocks are saved forever, but validators don't need to keep the whole history to sign new blocks :)