I introduced srtool in a previous article. While the first implementation filled a gap and allowed for the first time users to verify substrate runtime wasm blobs, there was still work to do to improve the user’s experience.
1. Current verification process Up to now, the verification process looked like:
a runtime dev works on some changes
he builds the new runtime locally, preferably using srtool in order to get the SHA256 of the new wasm blob right away
Unlike all other Blockchains, Polkadot (based on Substrate) allows on-chain protocol upgrades without requiring the node operators to do anything but to keep their node up and running.
If you know everything about Substrate Runtime, you may jump to the Installation section.
In order to achieve this, Polkadot stores its runtime executable as a WASM blob in its own storage. If the WASM blob is replaced, the new runtime kicks in and all the nodes start using it, altogether.