BAM: Solana’s Block Builder Era

Solana had a pretty solid run last week (can’t really say the same for $PUMP). But the stuff that actually drove the momentum pushing SOL? That, more often than not, gets buried under memes and timeline noise.

The best bits of crypto rarely make it to the front page, unless you’re reading blocmates, of course.

With that said, if you’ve ever wondered how blockchains decide which transaction gets included where, congrats,  you’ve bumped up against one of the most underappreciated power centers in crypto, block building.

Ethereum made it a battleground with MEV, relays, and builders. Solana didn’t really have a dedicated layer for it. But now it does.

And it’s rolling in with a BAM! No, quite literally, that’s what it’s called.

What is BAM?

Jito Labs just announced the launch of BAM, or Block Assembly Marketplace. It's Solana’s first serious attempt to rethink how blocks are assembled, transactions are sequenced, and value is distributed.

Traditionally, validators in Solana would grab transactions from the mempool and jam them into blocks. It was simple,fast, but exploitable.

BAM breaks this open by introducing a dedicated off-chain layer of block builders, powered by Trusted Execution Environments (TEEs). A quick primer: TEEs are essentially private enclaves that encrypt and simulate transaction bundles.

How BAM actually works (without breaking Solana)

BAM doesn’t rip up Solana’s base layer or ask for protocol changes. It’s a modular transaction layer built on top of Solana. It introduces secure, programmable sequencing without requiring any changes to the base protocol.

Here’s how the flow works:

1. Transaction submission
Traders, protocols, and apps submit transactions directly to BAM nodes, which act as dedicated entry points for secure sequencing.

2. Sequencing via Trusted Execution Environments (TEEs)
Each BAM node operates inside a TEE hardware that keeps transaction data encrypted during processing.
The node filters and sequences the incoming transactions privately, without exposing the mempool to third parties. This eliminates common MEV tactics like frontrunning and sandwiching.

3. Plugin layer for custom logic (ACE)
Developers can attach custom plugins to BAM Nodes. These plugins define how transactions should be ordered within specific applications via something called Application-Controlled Execution (ACE).

A few examples:

• Oracles can be prioritized to update prices before trades.
• Perp protocols can sequence liquidations before market orders.
• LPs can be given priority access in AMM batches.

4. Execution and Attestation
Once sequenced, the transactions are passed to the active Solana validator (the “leader”) for execution. Both the BAM Node and validator generate attestations - cryptographic proofs confirming the integrity of the sequencing and execution.

Attestations are published and publicly verifiable. This allows anyone to audit how transactions were ordered and processed, adding a layer of transparency to the execution pipeline.

BAM operates independently of Solana’s core consensus. It’s already being adopted by validators like @triton_one and @heliuslabs and integrated with projects like @DriftProtocol and @PythNetwork.

BAM’s impact on Jito and Solana

Solana nails speed and cost, but it’s had a lingering problem: MEV.

Bots and validators front-run or reorder transactions for profit, often at the user’s expense. It’s a drag on trust and a blocker for serious DeFi and institutional adoption.

BAM changes that.

It introduces a private, encrypted mempool where transactions are hidden until execution. That alone kills sandwich attacks. Add in verifiable sequencing and app-level ordering logic, and suddenly, MEV shifts from pure extraction to structured value creation.

This makes the network cleaner for retail and safer for pros. It reduces spam, gives developers control, and offers users predictable execution.

Institutional players get what they’ve been waiting for: auditability and fairness. No more shadow games, think onchain order books and perps, minus the L2 baggage.

There’s also a clear value loop.

Apps can monetize custom sequencing logic through plugins. Fees flow to BAM operators, validators, stakers, and ultimately to the Jito DAO treasury, reinforcing $JTO’s economic model.

BAM is built right into Jito’s long-term roadmap: supported, maintained, and iterated on by Jito Labs themselves.

Every auction, every bundle, every byte of value that flows through BAM directly strengthens the DAO.

You can track the growing flow of BAM fees straight into the treasury on Dune.

Big picture: Solana has always been fast. But now it’s adding market structure and value feedback loops.

BAM gives Solana a real block-building layer. And Jito makes sure it pays the people, not just the protocols. And you have probably heard it a thousand times before, but it’s true: the success of Jito is the success of Solana, and inversely.

Call it a flywheel. Or a revenue loop. Either way, it’s spinning.

The BAM roadmap

BAM’s north star is a block-building layer that’s efficient, transparent, and truly decentralized, while creating new revenue streams for validators, developers, and token holders.

The rollout is phased, with deliberate steps to test, scale, and eventually hand off control to the broader Solana ecosystem.

Phase 1: Launch

Jito Labs will operate the initial set of BAM Nodes to ensure performance and security at the protocol level.

A small group of handpicked alpha validators, including Triton One, SOL Strategies, Figment, and Helius will run the BAM client. The target is a high single-digit share of total network stake early on.

Alongside this, Solana-native apps will begin testing custom sequencing logic via the first batch of plugins. These early integrations will validate real-world demand and revenue potential.

Phase 2: Scale

With initial functionality proven, the BAM Validator Set expands both in number and in geographic spread to reach 30%+ of Solana's total stake. BAM node operators will also diversify to improve censorship resistance and latency coverage.

At the same time, more plugin developers are expected to onboard, with the first wave of production-grade plugins going live. These begin routing fees through the BAM pipeline directly to node operators, validators, stakers, and ultimately the Jito DAO treasury.

This is the phase where BAM becomes hard to ignore: real yield, on-chain coordination, and composability across Solana’s core infrastructure.

Phase 3: Accelerate

BAM code will be open-sourced, turning it from a controlled launch into a permissionless platform. Third-party node operators will grow to over 50 globally distributed participants. This ensures not just robustness and decentralization, but also ultra-low latency for apps that need precision execution.

The validator network will be fully onboarded. SDKs and developer tooling will be available for anyone to build, test, and deploy custom sequencing logic in minutes, not months. At this point, BAM becomes an open market for blockspace innovation.

Governance, too, transitions fully to the community, with Jito Labs stepping back and decentralized governance taking over management of BAM’s future.

Concluding thoughts

The market might not be the best for some right now, and $PUMP hasn’t done anyone favors. But there’s always a bright side to it. Altseason seems to be around the corner, and your favourite (maybe?) L1 has been leveling up.

If Solana wants to go from fast chain for degens to infra for global markets, this is the move that makes it happen. BAM opens the door to serious on-chain order books, real-time oracle updates, and execution logic that was previously impossible without going off-chain or onto an L2.

We might as well be looking at another paradigm shift for Solana.