Steel on Boundless: Solidity without gas limits

Smart contracts have never had full context.

They can’t access historical state.

They can’t compute across multiple blocks.

They can’t react to events without relying on indexers or costly oracles.

And no matter what you’re building, there’s a hard ceiling you can’t break: Ethereum’s 30M gas limit.

EVM developers have been building in a tunnel: cut off from the past, unable to see across time, forced to trust third-party infrastructure, and always constrained by how much computation can fit in a single block.

Steel on Boundless changes that.

Steel is a ZK-coprocessor for the EVM that plugs right into Boundless. It offloads execution offchain, where you can aggregate data, run complex logic, or compute across time, then return just a tiny proof onchain. Your EVM contract can then verify it in constant gas, regardless of how much computation you do.

The three primitive beneath it all

Event logs as inputs, verified and trustless

Historical state from any block since Dencun

Multi-block logic that spans time ranges, not just single blocks

All offloaded off-chain. All verifiable on-chain. All while still using Solidity for your core logic.

This unlocks a new design space for EVM apps: Contracts that can extend beyond a single block, react to events, reason over history, and break free from block size limits.

A New Design Space for EVM Apps

Steel introduces three powerful capabilities that unlock new levels of expressiveness and intelligence:

Event-Powered Logic

Onchain events carry rich information: swaps, deposits, votes, liquidations. But they’re ephemeral. Once gone from client memory, contracts can’t see them. Indexers fill the gap, but introduce trust assumptions.

Steel lets you treat emitted events as verifiable inputs. It proves that a specific set of logs exists and returns them as data your contract can act on.

Historical State Queries

Contracts can only query current state. Accessing older state requires heavy archive infrastructure, or storing unnecessary data on-chain.

Steel gives contracts direct, verifiable access to any storage slot or balance from any block since the Dencun hard fork.

Think Across Blocks

Smart contracts traditionally evaluate state within a single block. If you need to track a moving average, sum deposits over time, or analyze block-by-block behavior, you’re stuck with costly workarounds. With Steel, you can compute over any range of blocks off-chain and return a single verifiable result on-chain, in constant gas.

Expand across Ethereum and OP chains

Using the newly audited R0-Helios lite client, you can now more trustlessly talk across chains using Steel. Helios, is a trustless, efficient, and portable multichain light client written in Rust that has been developed by a16z for the past few years allows you to retrieve more trustless block hashes from origin chains that can be used by Steel on other chains. Currently Helios supports ETH L1 and the OP Stack, making it easier than ever to compute across those chains using Steel.

Break Through the Block

Steel brings expressive, data-rich, multi-block logic to EVM developers, without the gas burden, infrastructure complexity, or trust tradeoffs that used to come with it.

Steel removes the execution boundaries of the EVM, enabling developers to scale far beyond the 30M block gas limit.

Deploy with Boundless

Build your application with Steel and let Boundless do the rest:

Strong Liveness: A global set of independent prover nodes races to publish every proof; if one drops, another picks it up, keeping your app live even during high traffic.

Competitive pricing, subsidized by PoVW: Nodes bid in an open market, and Proof-of-Verifiable-Work rewards offset costs, so you pay near-raw compute prices, often orders of magnitude below onchain gas.

Guaranteed proof delivery: Boundless proving is permissionless, each prover stakes collateral that’s slashed if they miss the deadline; the slashed funds immediately become a bounty that any other node (even one spun up in minutes) can claim by submitting the proof, so someone is always incentivized to finish the job.

Get started today

Steel documentation - Get started with one CLI command.

Developer Discord - Get technical support from the Boundless/RISC Zero team

The block is no longer a boundary. Welcome to Boundless.