> For the complete documentation index, see [llms.txt](https://docs.rome.builders/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.rome.builders/products/rome-sdk.md). # Rome SDK The Rome SDK provides typed Solidity interfaces for interacting with Solana programs from EVM smart contracts. It's the developer toolkit for building cross-runtime applications on Rome. ## SDKs Rome has SDKs for three audiences — app builders (TypeScript), contract developers (Solidity), and infrastructure operators (Rust). ### TypeScript SDK (`@rome-protocol/sdk`) **For dapp and frontend developers** — the SDK most app builders start with. [`@rome-protocol/sdk`](https://github.com/rome-protocol/rome-sdk-ts) wraps the Rome write path so a web app submits Rome transactions correctly: `submitRomeTx` (the correct write path plus gas/fee handling), PDA / ATA derivation, CPI `invoke` / `invoke_signed` encoders, precompile bindings, and a `/bridge` subpath. Repo-first install (npm publish pending): ```bash npm install github:rome-protocol/rome-sdk-ts#v0.2.1 ``` ```typescript import { submitRomeTx } from '@rome-protocol/sdk'; // Submit any Rome EVM write through the correct write path (handles gas/fee encoding). ``` The public reference apps — [rome-dex](https://github.com/rome-protocol/rome-dex) and [cardo](https://github.com/rome-protocol/cardo) — consume this SDK. **Both lanes, one SDK.** `submitRomeTx` is the EVM lane (MetaMask). For the **Solana lane** — a Phantom/Solana wallet driving your EVM app — `submitRomeTxSolanaLane` mirrors it: the user signs a Solana transaction and Rome runs it as an EVM transaction from their derived identity, with no EVM key. Value moves in and out through `buildFundLeg` / `buildSweepLeg` as an ERC-20 wrapper (e.g. `wUSDC`), not native `msg.value` — the synthetic sender holds nothing at rest — and a first-time synthetic is auto-provisioned on first use. See [Build a dual-lane app](/developer-guides/dual-lane-app.md) and [Call EVM from Solana](/developer-guides/call-evm-from-solana.md). ### Solidity SDK (`@rome-protocol/rome-solidity`) **For Solidity developers.** Provides the precompile interfaces, ERC-20/SPL wrappers, PDA derivation, and CPI utilities. The npm publish is pending; today you consume these from the public [`rome-solidity`](https://github.com/rome-protocol/rome-solidity) repo (git dependency or copied files). ```solidity import {ISystemProgram, ICrossProgramInvocation, IHelperProgram, IWithdraw} from "@rome-protocol/rome-solidity/contracts/interface.sol"; import {SPL_ERC20} from "@rome-protocol/rome-solidity/contracts/erc20spl/erc20spl.sol"; import {RomeEVMAccount} from "@rome-protocol/rome-solidity/contracts/rome_evm_account.sol"; ``` ### Rust SDK (`rome-sdk`) **For infrastructure operators.** A Rust workspace that handles transaction composition, Solana interaction, gas pricing, and block indexing. Used by the Proxy and Hercules. ## Solidity SDK: What's Included ### Precompile Interfaces Bind an interface to its precompile address: ```solidity ISystemProgram constant System = ISystemProgram(0xFF00000000000000000000000000000000000007); ICrossProgramInvocation constant Cpi = ICrossProgramInvocation(0xFF00000000000000000000000000000000000008); IHelperProgram constant Helper = IHelperProgram(0xFF00000000000000000000000000000000000009); IWithdraw constant Withdraw = IWithdraw(0x4200000000000000000000000000000000000016); // Cached track: ISplCached 0xff…05, IAssociatedSplCached 0xff…06, ISystemCached 0xff…04, IWithdrawCached 0xff…0b ``` ### SPL Token Operations Use `IHelperProgram` (`0xff…09`) for user-PDA-signed SPL primitives: ```solidity // Create the caller's ATA for a mint Helper.create_ata(user, mint); // Transfer SPL from the caller's PDA Helper.transfer_spl(to, tokens, mint); ``` On the cached track, the equivalent operations live on `ISplCached` (`0xff…05`) and `IAssociatedSplCached` (`0xff…06`). See `interface.sol` for all overloads; a contract uses one track consistently. ### PDA Derivation ```solidity // Derive a user's Solana PDA bytes32 userPda = RomeEVMAccount.pda(msg.sender); // Derive PDA with salt (for creating multiple PDAs per user) bytes32 pda = RomeEVMAccount.pda_with_salt(msg.sender, salt); // Find arbitrary PDA (bytes32 pda, uint8 bump) = SystemProgram.find_program_address(programId, seeds); ``` ### Cross-Program Invocation ```solidity // Call any Solana program ICrossProgramInvocation.AccountMeta[] memory accounts = new ICrossProgramInvocation.AccountMeta[](2); accounts[0] = ICrossProgramInvocation.AccountMeta(signerPda, true, true); accounts[1] = ICrossProgramInvocation.AccountMeta(targetAccount, false, true); CpiProgram.invoke(programId, accounts, instructionData); // Call with PDA signing CpiProgram.invoke_signed(programId, accounts, data, seeds); // Read account data (uint64 lamports, bytes32 owner, bool isSigner, bool isWritable, bool executable, bytes memory data) = CpiProgram.account_info(pubkey); ``` ### ERC-20 over SPL Tokens ```solidity // Deploy wrapper for any SPL mint ERC20SPLFactory factory = ERC20SPLFactory(FACTORY_ADDRESS); address wrapper = factory.add_spl_token_with_metadata(splMint); // Use the wrapper as standard ERC-20 SPL_ERC20 token = SPL_ERC20(wrapper); token.transfer(recipient, amount); uint256 balance = token.balanceOf(user); ``` ### Borsh Deserialization ```solidity import {Convert} from "@rome-protocol/rome-solidity/contracts/convert.sol"; // Parse Solana account data (little-endian Borsh format) (uint64 value, uint256 newOffset) = Convert.read_u64le(data, offset); (bytes32 pubkey, uint256 newOffset2) = Convert.read_bytes32(data, offset); ``` ### Metaplex Metadata ```solidity import {MplTokenMetadataLib} from "@rome-protocol/rome-solidity/contracts/mpl_token_metadata/lib.sol"; // Load token metadata from Metaplex MplTokenMetadataLib.Metadata memory meta = MplTokenMetadataLib.load_metadata( mintPubkey, mplProgramId, cpiAddress ); string memory name = meta.name; string memory symbol = meta.symbol; ``` ## Rust SDK: Architecture The Rust SDK is a Cargo workspace. Its core crates: | Crate | Purpose | | ------------------- | ------------------------------------------------------------------------------- | | `rome-sdk` | Core API: `Rome` struct, config, transaction types (RheaTx, RemusTx, RomulusTx) | | `rome-evm-client` | EVM rollup client, TxBuilder, ResourceFactory, emulator integration | | `rome-solana` | Solana tower, RPC client, transaction batching and tracking | | `rome-utils` | RLP, hex, JSON-RPC, authentication utilities | | `rome-obs` | OpenTelemetry observability (traces, metrics, logs) | | `rome-meteora` | Meteora DEX AMM pool adapters for gas pricing | | `rome-jito-bundler` | Jito bundle builder for atomic multi-transaction submission | ### Transaction Types ```rust // Single rollup transaction let rhea = RheaTx::new(signed_eth_tx); let mut tx = rome.compose_rollup_tx(rhea).await?; let sig = rome.send_and_confirm(&mut *tx).await?; // Cross-rollup atomic transaction let remus = RemusTx::new(vec![tx1, tx2]); let mut tx = rome.compose_cross_rollup_tx(remus).await?; // Cross-chain atomic transaction (EVM + Solana) let romulus = RomulusTx::new(eth_txs, sol_ixs); let mut tx = rome.compose_cross_chain_tx(romulus, signers).await?; ``` ### Resource Pooling The SDK pools Solana keypairs (payers) and holder account indices for parallel transaction submission: ```rust let resource = resource_factory.get().await?; let payer = resource.payer(); // Solana keypair let holder = resource.holder(); // Holder account index // Resource automatically returned to pool on Drop ``` ## SDK Roadmap ### Built and Working * SPL Token wrappers and precompile interfaces * Meteora DAMM v1 swaps via CPI * Oracle Gateway V1 + V2 (Pyth Pull, Switchboard V3) * System Program helpers, Borsh deserialization * ERC20SPL Factory + bridge contracts ## What's Next * [Deploy Solidity](/developer-guides/deploy-solidity.md) — deploy your first contract using the SDK * [Call Solana from EVM](/developer-guides/call-solana-from-evm.md) — use CPI to interact with Solana programs * [Contract Addresses](/reference/contract-addresses.md) — deployed SDK contract addresses --- # Agent Instructions This documentation is published with GitBook. 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