svm development

QoreChain includes a Solana Virtual Machine (SVM) execution environment, allowing developers to deploy and execute BPF programs using familiar Solana tooling. The SVM module exposes a Solana-compatible JSON-RPC interface on port 8899.

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Overview

The x/svm module provides:

• BPF program deployment and execution

• Data account creation and management

• A Solana-compatible JSON-RPC endpoint

• Bidirectional address mapping between QoreChain and Solana address formats

• Compute budget metering and rent-based storage economics

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JSON-RPC Endpoint

Property	Value
Default URL	http://localhost:8899
Compatibility	Solana JSON-RPC (subset)

Supported Methods

Method	Description
getAccountInfo	Retrieve account data and lamport balance
getBalance	Get account balance in lamports
getSlot	Current slot number
getMinimumBalanceForRentExemption	Minimum balance for a given data size
getVersion	SVM runtime version info
getHealth	Health check for the SVM endpoint

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1

Deploy a BPF Program

Compile your Solana program to a BPF shared object, then deploy it to QoreChain:

Deploy the compiled program

qorechaind tx svm deploy-program ./my_program.so \
  --from mykey \
  --gas auto \
  --gas-adjustment 1.3 \
  -y

The transaction response includes the program ID in base58 format.

2

Execute an Instruction

Call an on-chain BPF program with instruction data:

Execute instruction

qorechaind tx svm execute <program-id-base58> <data-hex> \
  --from mykey \
  --gas auto \
  -y

Parameter	Format	Description
program-id-base58	Base58 string	The deployed program's address
data-hex	Hex-encoded bytes	Serialized instruction data

3

Create a Data Account

Programs often need accounts to store state. Create one with a specified size and owner:

Create data account

qorechaind tx svm create-account <owner-base58> <space> <lamports> \
  --from mykey \
  --gas auto \
  -y

Parameter	Description
owner-base58	The program that owns this account (base58)
space	Size of the data field in bytes
lamports	Initial balance (must meet rent exemption minimum)

Query the minimum rent-exempt balance for a given size:

RPC: getMinimumBalanceForRentExemption

curl -X POST http://localhost:8899 \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "getMinimumBalanceForRentExemption",
    "params": [1024]
  }'

4

Using @solana/web3.js

The Solana JavaScript SDK works directly with the QoreChain SVM endpoint:

Example using @solana/web3.js

import { Connection, PublicKey } from "@solana/web3.js";

const connection = new Connection("http://localhost:8899");

// Check health
const health = await connection.getHealth();
console.log("SVM health:", health);

// Get slot
const slot = await connection.getSlot();
console.log("Current slot:", slot);

// Get account info
const pubkey = new PublicKey("YourBase58ProgramId...");
const accountInfo = await connection.getAccountInfo(pubkey);
console.log("Account data:", accountInfo);

// Get balance
const balance = await connection.getBalance(pubkey);
console.log("Balance (lamports):", balance);

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Address Mapping

QoreChain maintains a bidirectional address mapping between native Bech32 addresses (qor1...) and Solana-style base58 addresses:

Direction	Example
Native to SVM	qor1abc...xyz maps to a deterministic base58 address
SVM to Native	Base58 program addresses map back to qor1... equivalents

The mapping is deterministic and managed by the x/svm module. Both representations refer to the same underlying account.

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Rent Model

The SVM module uses a rent-based storage model to prevent state bloat:

Parameter	Value
Lamports per byte per year	3,480
Rent exemption multiplier	2.0
Collection frequency	Each epoch

• Accounts with a balance above 2 * (data_size * 3480 / seconds_per_year) in lamports are rent-exempt and are never charged.

• Accounts below the rent-exemption threshold are charged rent each epoch. If the balance reaches zero, the account is purged.

Best practice: Always fund data accounts above the rent-exemption minimum to avoid unexpected account deletion.

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Compute Budget

Each instruction execution is metered with compute units:

Parameter	Value
Max compute units per instruction	1,400,000
Max CPI (cross-program invocation) depth	4
Max program size	10 MB
Max account data size	10 MB

Programs that exceed the compute budget are halted and the transaction is reverted.

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Parameters Summary

Parameter	Value
max_program_size	10 MB
max_account_data_size	10 MB
compute_budget_max	1,400,000 CU
max_cpi_depth	4
lamports_per_byte_year	3,480
rent_exemption_multiplier	2.0
JSON-RPC port	8899

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Cross-VM Interoperability

SVM programs can communicate with EVM and CosmWasm contracts through the asynchronous cross-VM message path:

Cross-VM call example

qorechaind tx crossvm call \
  --source-vm svm \
  --target-vm evm \
  --target-contract 0x1234...abcd \
  --payload '...' \
  --from mykey \
  -y

Messages are queued and processed by the EndBlocker. See Cross-VM Interoperability for details on the message lifecycle and timeout behavior.

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Next Steps

• Cross-VM Interoperability -- Communication between SVM, EVM, and CosmWasm

• EVM Development -- Solidity smart contracts on QoreChain

• CosmWasm Development -- Rust-based WebAssembly contracts