The comparing privacy solutions in DeFi right now

MEV doesn't get talked about enough relative to how much it actually costs people.

Unless you're a whale, most traders know sandwich attacks exist in the abstract but have no idea how much they're losing to them or what the realistic protection options are.

There are several approaches worth knowing about and they work very differently from each other.

The problem

On a public blockchain, your transaction is visible from the moment you submit it until it's confirmed.

Block producers control ordering. Searcher bots scan the pending pool, identify profitable opportunities, and act in the gap between submission/confirmation.

The classic mechanic is a sandwich: a bot sees your pending swap, buys the same asset ahead of you, your trade executes at a worse price, the bot sells immediately after.

Worth noting: not all MEV is purely extractive. The same infrastructure can be used to intercept exploits mid-attack or close arbitrage gaps.

But for the average trader, the interaction is mostly one-directional.

Flashbots / private RPCs

Routes your transaction directly to block builders through a private channel rather than broadcasting to the public mempool. You don't change your wallet, you change the RPC endpoint. Billions of dollars of transactions have gone through this on Ethereum. Requires manual opt-in, so most users never bother.

• Transaction routed directly to block builders, never entering the public mempool
• The relay operator retains some visibility — trust is transferred, not eliminated

CoW Swap

Instead of submitting a raw transaction, you sign an intent describing what you want to trade. A network of bonded solvers competes to find the best execution path across onchain liquidity, private market maker inventory, and peer-to-peer matching. When two users want opposite sides of the same trade, CoW settles them directly with no mempool exposure.

• Solver competition can produce better pricing than standard DEX routes
• Protection is structural rather than cryptographic — delegated execution, not a sealed transaction

Railgun

Uses zk-SNARKs to shield token balances and transaction history inside an onchain privacy pool. Shielded assets sit in encrypted smart contracts deployed directly on various chains, no separate network or bridge required. From the outside, activity is not traceable to the user.

• Most comprehensive at the asset level — supports ERC-20s, NFTs, and private DeFi interactions
• Shielding and unshielding adds friction and a real proficiency bar

Near Intents

An outcome-based protocol where users specify what they want and solvers compete to fulfill it. Has a confidential mode that routes through a TEE-based bridge where token pairs, order sizes, and timing stay out of the public mempool until after execution. Standard intents without confidential mode still broadcast to solvers without privacy guarantees.

• Transaction details remain private and only become visible on the public chain after execution
• Confidential mode is opt-in — standard intents carry no privacy guarantees

Privana Finance

Execution happens inside a hardware enclave before anything reaches public infrastructure. Swap intents are signed inside the enclave, the private key never leaves it, and the enclave handles automation and rule-based execution without the user needing to be present.

• No relay to trust, no shielding step to manage
• Custody stays with the user throughout

These approaches sit on a spectrum from simple workarounds to cryptographic enforcement to hardware-sealed execution. Which one makes sense depends on who you are and what goals you have.

Disclosure: I am affiliated with Privana.