In House of ZK Radio #86, @robin_linus (@ZeroSync_) walks through why he created BitVM and how it actually works. Robin first explains how Bitcoin was designed as a peer-to-peer payment system, but 10-minute blocks and ~4MB per 10 minutes are nowhere near enough for global usage. Rather than turning Bitcoin into another smart contract chain, he wanted a way to get zkRollup style bridges and L2s on Bitcoin using only existing opcodes. That led to BitVM’s core idea: optimistic verification - instead of fully verifying a SNARK on-chain, you only need to be able to disprove an invalid proof, like pointing to two conflicting cells in a bad Sudoku solution. He then goes on to explain how BitVM turns Bitcoin Script’s very limited, 32-bit, no-multiplication environment into a general verification layer by structuring the system around two roles: an operator who posts claims, and challengers who can succinctly prove fraud. The trust model shifts from “honest majority” to “one honest challenger is enough”, opening the door to trust-minimized bridges and more expressive L2s without a soft-fork. Watch the full episode to go deeper into BitVM’s evolution (BitVM1 → BitVM2 → BitVM3), garbled circuits and Glock, why he calls BitVM “a pile of hacks on hacks”, and how all of this fits into the broader roadmap for scaling Bitcoin in a Bitcoin-native way: