BitVM is quietly evolving:
The new design, BitVM3, drastically reduces onchain costs in the case of a challenge (by ~1000x).
In earlier versions, while challenging was permissionless, the high costs meant only a few well-capitalized entities could realistically participate in the process.
BitVM3 may change that, opening the door to a broader set of challengers.
The tradeoff: garbled circuits introduce a multi-terabyte offchain setup.
Reducing this overhead is an active research area and likely to see improvements.
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