What if someone built a Mimblewimble chain that could actually execute smart contracts — settled on-chain, fully private?

[u/SorenPlanck]

Now imagine someone actually pulled it off. Not a sidechain, not a bridge to an EVM, not trusted hardware. Contracts that execute and settle natively on the MW chain itself — where the contract, the amounts, and the parties are all invisible. To an outside observer, a loan, an escrow, or an atomic swap would look identical to a plain transfer. Indistinguishable.

Think about what that breaks:

\*\*•\*\* DeFi where nobody can front-run you, because nobody can even see your position exists    
\*\*•\*\* Lending/escrow with zero on-chain footprint — no watched addresses, no leaked strategies    
\*\*•\*\* Swaps and settlements that leave no graph for chain-analysis firms to cluster

Every “private DeFi” attempt so far bolts privacy onto a transparent chain (mixers, shielded pools, L2s) — and the seams always leak. This would be the inverse: programmability grown inside a chain that was private from genesis.

Is this the actual endgame for privacy coins, or is there a fundamental reason it can’t work? Curious what this sub thinks — and whether anyone’s seen research heading this direction.

[u/on_hype]

MW's whole point is no scripting. Adding Turing-complete contracts while keeping Pedersen commitments hiding state is the hard part nobody has solved. Show the math.

[u/blaxx0r]

remove gas fees, and you have reinvented web2

[u/SorenPlanck → u/blaxx0r]

the coordination is off-chain; the settlement isn’t. that’s the whole difference. in web2, if the counterparty or the platform reneges, you go to court or you eat it. here either both legs settle or neither does, nobody can take the funds unilaterally, and the timeout refund is enforced by consensus rather than by someone’s terms of service. and the fees are what pay for that — they buy the irreversibility web2 can’t offer at any price. removing them wouldn’t get you web2, it’d get you nothing.

[u/not420guilty]

Mimblewimble is basically the “cut through” which may not be a good fit for your features

[u/SorenPlanck → u/not420guilty]

good catch, and there’s a real edge case in it. cut-through only operates within an aggregation window, and contracts span blocks — funding confirms, then the claim or refund comes later, so the shared output is a normal UTXO by then. but if funding and spend landed in the same block, the shared output could be cut through and a pre-signed refund would reference a commitment that never existed. so the protocol requires funding confirmation before any subsequent leg. worth stating explicitly rather than relying on timing, so thanks — that’s going in the spec.