What a Signature Can See
A Bitcoin signature doesn't sign the transaction. It signs a message — the sighash — assembled from only the fields its flag chooses to SEE. Everything left BLIND, anyone can change after you sign. A Feynman-style idea-book, from a dinner table to a wall — with a playground you can touch.
▶ Open the SIGHASH playground🎛 Interactive playground
Turn the two sighash dials, watch every field go SEE or BLIND on a real transaction, and tamper a field to prove it. Real BIP-341, no network.
📖 The book
Nine short chapters: a dinner → the paper-strip → covenants → can you see your neighbour's note? → the wall.
Read on
Technical blog posts: What a Bitcoin Signature Actually Signs ·
When Two Signatures Collide
Companion signet series: medium.com/@aaron.recompile
Specs: BIP-341 · BIP-143 · verified on signet
Companion signet series: medium.com/@aaron.recompile
Specs: BIP-341 · BIP-143 · verified on signet
