Taproot
Schnorr signatures and Merkelized scripts — Bitcoin's smoothest major upgrade.
Taproot combined Schnorr signatures (BIP 340), Merkelized Alternative Script Trees (BIP 341), and Tapscript (BIP 342) into a single soft fork activated November 14, 2021 at block 709,632. Pieter Wuille and collaborators had been developing the proposal since 2018.
Taproot makes complex transactions (multisig, Lightning channel opens/closes, timelocks) indistinguishable from simple payments on-chain — improving privacy. Schnorr signatures enable signature aggregation, reducing transaction size and fees for cooperative spends.
Unlike SegWit, Taproot faced minimal controversy. Miners locked it in at block 687,284 in June 2021 with over 90% signaling support. The five-month delay between lock-in and activation gave the ecosystem time to prepare wallet and exchange support.
Key Benefits
Outcome
Activated without incident. Gradual wallet adoption enabled cheaper multisig, improved Lightning privacy, and opened the door for more sophisticated Bitcoin applications.