> For the complete documentation index, see [llms.txt](https://docs.load.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.load.network/load-hyperbeam/evm-1.0-device.md).

# \~evm\@1.0 device

## About

The `@evm1.0` device: an EVM bytecode emulator built on top of Revm (version [v22.0.1](https://github.com/bluealloy/revm/releases/tag/v69)).

The device not only allows evaluation of bytecode (signed raw transactions) against a given state db, but also supports appchain creation, statefulness, EVM context customization (gas limit, chain id, contract size limit, etc.), and the elimination of the block gas limit by substituting it with a transaction-level gas limit.

{% hint style="warning" %}
***This device is experimental, in PoC stage***&#x20;

Live demo at [ultraviolet.load.network](https://github.com/loadnetwork/load_hb/blob/main/native/load_revm_nif/ultraviolet.load.network)
{% endhint %}

## Technical Architecture

`eval_bytecode()` takes 3 inputs, a signed raw transaction (N.B: chain id matters), a JSON-stringified state db and the output state path (here in this device it's in [./appchains](https://github.com/loadnetwork/load_hb/blob/main/native/load_revm_nif/appchains))

```rust
#[rustler::nif]
fn eval_bytecode(signed_raw_tx: String, state: String, cout_state_path: String) -> NifResult<String> {
    let state_option = if state.is_empty() { None } else { Some(state) };
    let evaluated_state: (String, String) = eval(signed_raw_tx, state_option, cout_state_path)?;
    Ok(evaluated_state.0)
}

#[rustler::nif]
fn get_appchain_state(chain_id: &str) -> NifResult<String> {
	let state = get_state(chain_id);
    Ok(state)
}
```

<figure><img src="/files/CCuapcZpGC3AbQbMEF8i" alt=""><figcaption></figcaption></figure>

### References

* device source code: [native/load\_revm\_nif](https://github.com/loadnetwork/load_hb/tree/main/native/load_revm_nif)
* hb device interface: [dev\_evm.erl](https://github.com/loadnetwork/load_hb/blob/main/src/dev_evm.erl)
* nif tests: [load\_revm\_nif\_test.erl](https://github.com/loadnetwork/load_hb/blob/main/src/load_revm_nif_test.erl)
* ao process example: [evm-device.lua](https://github.com/loadnetwork/load_hb/blob/main/test/evm-device.lua)


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.load.network/load-hyperbeam/evm-1.0-device.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.
