Building secure obfuscation turns out to be extremely difficult. The ideal version proved impossible in 2001, sending researchers to pursue weaker iO goals instead, but the nearly 20-year effort was full of failures. The good news these days is that iOs can now be built with reasonable security assumptions.
The downside, however, is that the runtime is, in Buterin’s words, “galactic.” Efficient in theory, but ridiculously slow in practice.
Buterin compared that moment to the situation around 2010, before years of optimization transformed SNARK, the zero-knowledge proof that is now central to Ethereum’s scaling, from a curiosity to a working infrastructure. Obfuscation could follow the same path from theoretical breakthrough to usable tool, even if it is hopelessly expensive to do once today.
Privacy coins like Monero (XMR) are already hiding things on the live blockchain, so why would Buterin treat this as unresolved? Because they’re hiding something different. Monero hides transaction data, including who paid whom and how much, through ring signatures, stealth addresses, and secret amounts.
Obfuscation in Buterin’s sense hides the logic of the program, the code itself, rather than the data flowing through it. As he says, iO hides code, not data. Monero has been working on transactional privacy for over a decade, but program obfuscation has never been performed in production. The purpose of his post is to fill that gap.
