Tapscript
Tapscript is the scripting language used for taproot script-path spends.
It shares most operations with legacy and segwit Bitcoin Script but has a few differences:
- 
    
OP_CHECKMULTISIGandOP_CHECKMULTISIGVERIFYare replaced by aOP_CHECKSIGADDopcode. - 
    
Many previously disabled opcodes are redefined to be
OP_SUCCESSopcodes that unconditionally render the entire script valid to simplify soft fork upgrades. - 
    
Signature hashes are calculated differently than in legacy script or BIP143 v0 segwit.
 
Primary code and documentation
Optech newsletter and website mentions
2021
- Bitcoin Core #21365 allows the wallet to create signatures for tapscript spends
 - Using backup tapscript spending paths to recover from crypto breaks
 
2020
- 2020 year in review: Taproot, tapscript, and schnorr signatures
 - Bitcoin Core #19953 merged with consensus implementation of BIP342
 - Bitcoin Core #16902 fixes an inefficiency in OP_IF related opcodes
 - btcdeb adds 
tapcommand for experimenting with taproot and tapscript 
2019
- 2019 year-in-review: taproot and tapscript
 - Discussion about position commitments using signature-checking opcodes
 - Bitcoin Optech schnorr/taproot workshop
 - Announcement of structured taproot review (including tapscript)
 - Update on changes to schnorr, taproot, and tapscript
 - Tapscript resource limits
 - BIP322 signmessage forward compatibility
 - Executive briefing: Taproot and Tapscript
 - Overview of Taproot and Tapscript
 - Extended summary of bip-taproot and bip-tapscript
 
See also
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