Ben, CEO of Harmonic, joins the show to discuss block building competition on Solana. Ben has a background in quantitative trading, having interned at Akuna Capital and Citadel Securities before moving into DeFi. He leads Temporal, the research organization behind multiple Solana products including Harmonic (block building), Humidify (market making), and Nozomi (transaction scheduling).

The conversation covers the current state of Solana's block building wars, with Ben defending Harmonic's approach against criticism from competitors like Jito. He argues that Solana was heading toward dangerous monopolization before Harmonic introduced competition. The discussion explores technical details around transaction ordering, the upcoming MCP (Multiple Concurrent Proposers) protocol, and Ben's vision for DeFi-native market structures that reject traditional finance approaches.

From TradFi to DeFi: The Speed and Transparency Advantage

Ben's transition from traditional HFT to DeFi began in early 2021 when he discovered Solana's transaction speed, saying "the few that landed at the time were incredibly fast, incredibly, incredibly fast."

The appeal of DeFi lies in creating "an environment that's open, transparent, and permissionless" versus traditional markets that are "largely closed, extremely high barrier to entry."

Solana has achieved the vision where "the cheapest place to buy Solana is on Solana," with retail getting tighter spreads than major centralized exchanges through prop AMMs.

Harmonic's Mission: Preventing Solana Monopolization

"The network was obviously on track to be largely monopolized by a single actor" - Ben explains Harmonic's core motivation to maintain competition.

Monopoly control would turn "Solana into a centralized exchange" where a single actor "can pick and choose winners, they can squeeze everyone on fees."

Harmonic aims to eliminate rate limits entirely within months, currently offering unlimited TPU access with plans to extend this to bundles and revert-protected transactions.

The team supports multiple concurrent builders where "different block builders are probably good in different scenarios" and validators can choose the best block according to their preferences.

Defending Against IBRL Criticism and Technical Metrics

Ben dismisses Jito's IBRL dashboard as flawed marketing, explaining "I could run a FIFO block that schedules transactions first in, first out... The IBRL dashboard would give this block builder on harmonic a zero."

The IBRL metric uses POH ticks which "are completely irrelevant and doesn't say anything about when the transaction was included," and POH is being eliminated in Alpenglow 4.1.

"RevStrat validators will broadcast POH ticks more consistently than a FIFO block builder would on harmonic" - demonstrating the metric's fundamental flaw.

Market Structure Success Despite Multiple Schedulers

Solana currently operates with "8-9 different schedulers" yet achieves "single-digit basis points, sometimes sub-single-digit" spreads on major pairs like SOL-USDC.

Multiple institutional market makers including Winter Mute are "actually all doing very well on Solana" using various transaction landing products to solve execution challenges.

"There's not really a statistically significant difference between clients" when examining five-second markouts across different block builders.

The success proves that "you need a single scheduler" is a "complete red herring" and "complete marketing from people that want something."

MCP: Censorship Resistance vs. Latency Trade-offs

"Censorship resistance" is the one property of MCP that "basically outweighs all the other things MCP does" despite other largely negative effects.

MCP will "guaranteed to increase latency for landing of transactions" because "you have multiple proposers all over the world and they all have to reconcile state with each other."

Current validators have "undisputed monopoly over what happens in that 1.6 seconds" including potential censoring, which MCP could address.

Ben remains neutral until seeing specific proposals: "I think I would be for the right proposal. I think I would be against the wrong proposal."

DeFi-Native Future: Rejecting TradFi Market Structure

"I do not think that DeFi will move toward TradFi" - Ben advocates building systems specifically designed for decentralized networks rather than importing traditional structures.

"The clob was invented for a world where everyone is co-located" but "Solana is a completely different system than NASDAQ" requiring DeFi-specific solutions.

The solution involves "market makers running more and more of their logic on chain" where "execution, that reaction is actually still instant because your logic as a market maker is running on chain."

As described in Asynchronous Market Queues, applications can handle their own ordering without special schedulers while maintaining composability, representing the future of DeFi market structure.