BAM (Block Assembly Marketplace)

BAM - Block Assembly Marketplace - is Jito Labs next-generation transaction scheduling system for Solana. Announced July 2025 and launched on Solana mainnet September 25, 2025, BAM moves transaction scheduling entirely outside the validator and into a distributed network of tamper-proof hardware nodes, making the ordering rules programmable by applications themselves. Lucas Bruder, CEO of Jito Labs, leads the project. BAM extends the Jito-Solana validator client, uses Jito community channels, and routes fee revenue to the Jito DAO treasury. It is best understood as Jito next chapter: a new operational mode validators opt into alongside the existing Block Engine. The Problem BAM Addresses: Solana transaction supply chain has long been partially opaque. Validators can observe pending transactions before including them in a block, enabling sandwich attacks where an adversary front-runs a user trade. The Jito Block Engine reduced this somewhat, but the scheduler still ran inside the validator where monitoring and manipulation remained theoretically possible. BAM reframes the problem: what if the entity ordering transactions never had the ability to act on what it sees? Trusted Execution Environments: BAM nodes run inside AMD SEV-SNP hardware enclaves. Transactions submitted to BAM enter this environment encrypted, are scheduled there, and emerge as ordered microblocks that validators execute in strict FIFO sequence - no reordering permitted after the TEE has produced its output. The hardware enclave produces cryptographic attestations proving the scheduling algorithm ran faithfully and that no transaction was selectively moved for extraction. AMD hardware acceleration keeps the computational overhead at two to five percent. BAM nodes communicate with validators over bidirectional gRPC streams and deliver signed attestation records alongside ordered batches, creating an immutable audit trail. Validator Integration: Validators add BAM support by appending a --bam-url flag pointing to a BAM Node endpoint. They choose among three operational modes at runtime via admin RPC - standard Agave, Jito Block Engine, or BAM - without requiring a restart. BAM provides fifteen regional endpoints globally including Amsterdam, Frankfurt, Singapore, and Tokyo. Validators not yet in the leader schedule maintain persistent connections so handoff is immediate. The initial mainnet launch validators were Figment, Helius, SOL Strategies, and Triton One. By September 2025, 340 validators were connected and 116 million SOL representing 27.7 percent of total Solana stake flowed through BAM-connected validators. By June 2026, a majority of Solana validators by count were running BAM with the Solana Foundation reporting roughly 33 percent of network stake. FireBAM serves validators running Firedancer or Frankendancer, Jump Trading independently implemented Solana client covering roughly twelve percent of the network. Plugins and Application-Controlled Execution: BAM plugin system is its most distinctive capability beyond privacy. Plugins are scheduling modules that hook directly into BAM and apply custom sequencing logic before transactions reach validators - a capability called ACE, Application-specific Controlled Execution. The Maker Priority Plugin illustrates this: price update transactions are elevated to the top of each 50ms batch, stale quotes between batches are deduplicated automatically, and submissions are validated before entering the pipeline. A market maker or oracle can guarantee its price feed lands before any trades execute against it, without relying on validator goodwill or tipping races. Broader plugin use cases include cancel-before-take policies for on-chain orderbooks, just-in-time oracle updates via Pyth, time-in-force enforcement, liquidation sequencing priority, and dark pool execution. Early application integrators include Drift Protocol, Pyth Network, and DFlow. Rollout and Business Model: BAM deploys in three phases. Launch phase: BAM nodes operated exclusively by Jito. Scale phase: governance directs a broader set of node operators. Accelerate phase: code is open-sourced and any operator can run a BAM node permissionlessly. Plugin fees flow to BAM node operators, validators, stakers, and the Jito DAO treasury. A Jito Improvement Proposal plans to redirect 100 percent of Block Engine and BAM protocol fees to the DAO treasury. The Jito DAO earned approximately four million dollars in Q2 2025 from existing Block Engine fees. Bruder has estimated BAM could generate an additional 15 million dollars annually through plugin and marketplace fees. Rakurai, a competitor that raised 11 million dollars led by Pantera Capital and announced two days before BAM mainnet launch, confirms the segment is actively contested. Approximately 40 percent of Ethereum mainnet blocks already use TEE-based construction via Flashbots suggesting meaningful precedent. Risks: Centralization is the primary concern. If early node operator economics create barriers to entry, a small number of builders could dominate Solana block production, mirroring three-builder concentration on Ethereum. AMD SEV-SNP has documented hardware vulnerabilities including CVE-2024-56161, and reliance on a single hardware vendor creates correlated failure risk. During the permissioned launch phase the system relies on selected operators not censoring or leaking metadata. BAM counterarguments: validators disconnect at any time with no switching costs; cryptographic attestations prove correct code execution; geographic redundancy across 100 or more globally distributed nodes limits correlated failures.