---
title: "proof"
description: "Fault proof crates covering the FPVM runtime, preimage oracle, driver, executor, and MPT verification."
source: https://basehub.org/crates/proof/overview/
---
The `proof` crate group implements Base's fault proof stack. The crates derive from [Kona](https://github.com/op-rs/kona) and cover proof generation, verification, and the Fault Proof Virtual Machine (FPVM) interface.

## Sub-crates

| Crate | Package Name | Purpose |
|-------|-------------|---------|
| [driver](/crates/proof/driver/) | `kona-driver` | Proof generation driver |
| [executor](/crates/proof/executor/) | `kona-executor` | Stateless block executor for proofs |
| [mpt](/crates/proof/mpt/) | `kona-mpt` | Merkle Patricia Trie for proofs |
| [preimage](/crates/proof/preimage/) | `kona-preimage` | Preimage oracle interface |
| [proof](/crates/proof/proof/) | `kona-proof` | Core proof logic |
| [std-fpvm](/crates/proof/std-fpvm/) | `kona-std-fpvm` | Standard FPVM runtime |
| [std-fpvm-proc](/crates/proof/std-fpvm-proc/) | `kona-std-fpvm-proc` | Procedural macros for FPVM |

## Role in the Architecture

The proof system enables trustless verification of L2 state transitions on L1. It:

1. Re-executes L2 blocks in a deterministic environment (`executor`)
2. Uses the Merkle Patricia Trie for state proof verification (`mpt`)
3. Interfaces with the preimage oracle for reading L1/L2 data (`preimage`)
4. Runs inside the Fault Proof Virtual Machine (`std-fpvm`)
5. Coordinates the proof generation process (`driver`, `proof`)

These crates compile to targets that run inside the FPVM (e.g., MIPS or RISC-V) for on-chain dispute resolution.

## Source

[`crates/proof/`](https://github.com/base/base/tree/main/crates/proof)