Transaction Types

Seismic transaction types and data structures in seismic-alloy

Core data structures for building, signing, encrypting, and submitting Seismic transactions.

Overview

seismic-alloy defines several transaction types that extend Alloy's standard Ethereum types with Seismic-specific encryption and privacy features. These types live in the seismic-alloy-consensus crate and are re-exported through the prelude.

Type Summary

Type	Description	Use Case
TxSeismic	Encrypted Seismic transaction (type 0x4A)	Privacy-preserving contract calls and state changes
TxSeismicElements	Encryption metadata and security parameters	Attached to every TxSeismic for key exchange, nonce, and expiry
TxSeismicMetadata	Additional Authenticated Data (AAD) context	AEAD encryption binding -- ensures ciphertext is tied to tx params
TxLegacyFields	Standard EVM transaction fields	Subset of tx fields used in AAD construction
SeismicTxEnvelope	Signed transaction wrapper enum	Network submission -- wraps all supported tx types including Seismic

Transaction Lifecycle

TransactionRequest           Build with seismic_foundry_tx_builder()
       |
       v
SeismicTransactionRequest    Mark as seismic with .seismic()
       |
       v
TxSeismic                    Filled by filler pipeline (nonce, gas, elements)
       |
       v
Signed<TxSeismic>            Signed with wallet private key
       |
       v
SeismicTxEnvelope::Seismic   Wrapped in envelope for RLP encoding
       |
       v
Network                      Broadcast via send_raw_transaction

Relationship Between Types

TxSeismic
├── chain_id, nonce, gas_price, gas_limit  (standard fields)
├── to, value, input                        (standard fields)
└── seismic_elements: TxSeismicElements
    ├── encryption_pubkey      (secp256k1 compressed, 33 bytes)
    ├── encryption_nonce       (12-byte AES-GCM nonce)
    ├── message_version        (0=RLP, >=2=EIP-712)
    ├── recent_block_hash      (freshness proof)
    ├── expires_at_block       (expiration block number)
    └── signed_read            (true for eth_call reads)

TxSeismicMetadata (for AAD construction)
├── sender: Address
├── legacy_fields: TxLegacyFields
│   ├── chain_id
│   ├── nonce
│   ├── to
│   └── value
└── seismic_elements: TxSeismicElements (same as above)

SeismicTxEnvelope (signed wrapper)
├── Legacy(Signed<TxLegacy>)
├── Eip2930(Signed<TxEip2930>)
├── Eip1559(Signed<TxEip1559>)
├── Eip4844(Signed<TxEip4844Variant>)
├── Eip7702(Signed<TxEip7702>)
└── Seismic(Signed<TxSeismic>)       <-- Seismic type 0x4A

Crate Location

These types are defined in seismic-alloy-consensus and re-exported through seismic-alloy-prelude:

use seismic_prelude::foundry::*;
// or directly:
use seismic_alloy_consensus::{TxSeismic, TxSeismicElements, TxSeismicMetadata};

Navigation

Page	Description
TxSeismic	The core Seismic transaction struct with all fields and methods
TxSeismicElements	Encryption parameters, builder methods, and crypto helpers
TxSeismicMetadata	AAD generation for AEAD encryption
SeismicTxEnvelope	Signed transaction wrapper for network submission

See Also

• Contract Interaction -- How to use these types in practice

• Shielded Calls -- Building transactions with .seismic()

• Encryption -- How encryption uses these types