Wasabi and Bitcoin Knots

Wasabi used to depend on Bitcoin Knots but since v2.6.0 that's not the case anymore. Bitcoin Knots provided an RPC feature that was not available in Bitcoin Core: GetBlock with previous outputs (verbosity 3), which was necessary to create the Wasabi custom compact filters without needing to keep a UTXO set as it did in previous versions. Additionally, both client and server made use of another exclusive RPC, GetMempoolInfo with fee rate histogram, which allowed Wasabi to estimate the fee rate better.

After Bitcoin Core merged the PR that extended the RPC GetBlock to provide previous outputs and the fee histogram was made optional in Wasabi, there is no more need for Bitcoin Knots. These changes were done long ago, much before the current discussion about OP_RETURN, and the reason behind them is purely technical.

Wasabi also redistributed Bitcoin Knots binaries as part of the Wasabi Wallet installers, something that makes no sense anymore in v2.6.0. Even though Wasabi v2.6.0 installers still come with Bitcoin Knots, why? Well, because the release was done while the OP_RETURN discussion started warming up, and we didn't want users to misinterpret our motives (You can see removing Knots was discussed months ago: https://github.com/orgs/WalletWasabi/discussions/13796).

The next Wasabi release will not redistribute Bitcoin Knots binaries because it is not a required dependency anymore and because Wasabi devs are not the ones to decide on behalf of Wasabi users what Bitcoin node they have to use.