Flowra Launches Open Orderflow Auction for Competitive Solana Block Building

Flowra, a Seoul-based infrastructure startup, launched its Open Orderflow Auction (OOA) on Solana on August 21, opening a competitive bidding layer for block production that the company says replaces the closed orderflow channels that currently define most of the network's block-building activity.

The OOA lets registered searchers (the bots and traders that identify profitable transaction orderings) bid openly for inclusion in a Solana block through a standard API. Flowra runs 200-millisecond mini-auction cycles in which participants submit bids, with the winning sequence passed to validators for block construction. The company launched the system alongside a Programmable Block Policy layer, which allows each validator to define its own transaction inclusion rules at the block-building level without requiring any change to Solana's consensus protocol.

How the Open Orderflow Auction Works

Each cycle runs on a 200ms cadence. Searchers must register to participate and submit bids through a documented API, and all bids are visible within the auction. The system pipes the winning transaction sequence to validators through a block engine that Flowra says operated at 99.999% uptime during its pre-launch pilot.

The approach differs from existing closed orderflow arrangements, where searchers typically negotiate private access to a validator's block assembly process or route bundles through a block engine with limited price discovery for either side.

Flowra tested the system on a single validator before the public launch. That validator's compute units per block rose from 84% of the network average to 101%, a 20.6% increase, according to Flowra's own reporting of the pilot. Block production remained at 100% during the test period.

Programmable Block Policy and Honeypot Compliance Integration

The Programmable Block Policy layer gives validators the ability to set per-validator rules governing which transactions and bundles can be included in block construction, independently of one another and without a protocol upgrade.

Flowra announced the compliance dimension of this layer in late July when it partnered with Honeypot, a compliance infrastructure provider, to integrate sanctions and risk screening into the policy layer. The integration screens transactions for sanctioned wallet addresses and network-level indicators including VPN services and proxy traffic before they reach block construction, as reported by Decrypt. Each validator defines its own compliance policy, preserving autonomy while giving regulated institutions a mechanism to meet their own requirements without waiting for network-wide decisions.

Entering a Block-Building Market Jito Has Reshaped

The context for Flowra's launch is a Solana block-building market that carries more economic weight than it did two years ago. After SIMD-0096 passed with 77% validator support in May 2024, validators began keeping 100% of transaction priority fees rather than burning half, as The Block reported. That change significantly raised the economic stakes of block ordering for both validators and searchers.

The three components of that daily revenue (base fees, priority fees, and Jito tips) averaged between 6,000 and 12,000 SOL per day over the past month, per Solana Compass analytics. Jito tips alone contributed 13–22% of total validator revenue on individual days during that period, with most days landing in the 16–22% range.

Jito JTO$0.462-3.6% Jito holds a dominant position in how that value flows on Solana. The Jito-Solana client accounts for a large majority of the network's active stake, and its block engine processes the bulk of the competitive orderflow on the network. In September 2025, Jito moved to modernize that infrastructure by launching its Block Assembly Marketplace (BAM) on Solana mainnet, an open-source system designed to make transaction sequencing transparent and verifiable using trusted execution environments.

Flowra enters that market with a distinct argument: that transparency should extend to the bidding process for block space itself, not only to how transactions are sequenced after bids are received. Its OOA publishes bids in real time and runs short auction cycles, which the company says improves price discovery compared to private orderflow arrangements. Raiku, a separate infrastructure startup that raised $13.5 million for guaranteed Solana transaction inclusion, targets a related problem (pre-confirmed transaction landing) from a different angle.

OOA Rollout: Institutional Validators First, Broader Scale Pending

Flowra says it is currently onboarding institutional-grade validators to the OOA, with a broader rollout planned as more operators integrate the system. The company has not disclosed how many validators are live on the OOA beyond the single pilot validator, and the pilot's single-validator scope means the compute unit gains have not yet been tested under multi-validator conditions or representative network load.

The OOA is described on flowra.wtf as open to any registered searcher. The company has not announced a token.