[PRESS RELEASE – New York, New York, November 5th, 2025]

Paradigm spearheads a $6 million seed round to introduce an innovative aggregation layer for exchanging block building, boosting speed, efficiency, and transparency amid Solana’s $72 billion validator sector.

Harmonic announces the debut of Solana’s first open block building infrastructure, enabling validators to source blocks from a variety of competing builders. This marks a significant leap toward decentralization, transparency, and validator-driven block generation on Solana.

Currently, in Solana’s framework, each validator sequentially assumes leadership roles, proposing blocks based on their scheduled slots. Despite its efficiency, this model centralizes block control to individual operators, favoring their stakes over overall performance. In contrast, Harmonic introduces a coordinated aggregation layer that dynamically routes builder proposals to validators, akin to a high-frequency trading system.

“Block building shouldn’t be a black box,” states Ben Coverston, Co-Founder of Harmonic. “Validators should decide what goes into a block, not a single operator or off-chain relay. Harmonic restores choice, competition, and transparency to block production on Solana. Our aim is to align Solana’s reliability with that of financial exchange engines, ensuring speed and uninterrupted operation.”

Through this aggregation mechanism, Harmonic continually aggregates block proposals from independent builders and presents them to validators in real-time. Validators can adopt personalized policies for block selection, including:

• MEV optimization: Maximize yield from arbitrage or priority fees.
• Content rules: Set inclusion or exclusion criteria for certain transactions or protocols.
• Policy alignment: Enhance fairness, compliance, or ecosystem preferences.

“Solana already excels in raw performance, processing thousands of transactions per second with sub-second finality,” remarks Jakob Povšič, Co-Founder of Harmonic. “With the introduction of open competition in block building, we advance this advantage even closer to the speed and reliability associated with global exchange infrastructure.”

By allowing multiple builders to contribute to block construction, Harmonic maintains competitive value discovery while ensuring validators retain full authority over their block choices. This parallel block sourcing approach paves the way for improved performance thresholds in Solana, which boasts one of the largest and fastest-expanding validator economies in the crypto space, with over $72 billion in active stakes across nearly 1,000 validators.

“Harmonic’s open aggregation framework converts Solana’s block production into a constantly optimized and competitive marketplace,” asserts Frankie, Investing and Research Partner at Paradigm. “This model aims to achieve exchange-grade performance, approaching Nasdaq’s reliability and throughput.”