2. Gateway SDK: Reading Ledger State

Overview

The Gateway SDK is a TypeScript client for the Radix Gateway API. It lets you query account balances, read component state, look up transaction history, and submit transactions – all the read/write operations your dApp frontend needs.

npm install @radixdlt/babylon-gateway-api-sdk

Setup

import { GatewayApiClient, RadixNetwork } from '@radixdlt/babylon-gateway-api-sdk'
 
const gatewayApi = GatewayApiClient.initialize({
  networkId: RadixNetwork.Mainnet,  // or RadixNetwork.Stokenet
  applicationName: 'My dApp',
  applicationVersion: '1.0.0',
  applicationDappDefinitionAddress: 'account_rdx...'
})

The SDK connects to the Radix Foundation's public Gateway by default. For production dApps with high traffic, consider running your own Gateway node or using a third-party provider.

Common Queries

Account Balances

const details = await gatewayApi.state.getEntityDetailsVaultAggregated(
  'account_rdx1c956...'  // account address
)
// details.fungible_resources — token balances
// details.non_fungible_resources — NFT holdings

Component State

const component = await gatewayApi.state.getEntityDetailsVaultAggregated(
  'component_rdx1cp...'  // component address
)
// Read state, 

Entity Metadata

const metadata = await gatewayApi.state.getAllEntityMetadata(
  'resource_rdx1t...'  // any entity address
)
// Returns: name, symbol, description, icon_url, etc.

Transaction Status

const status = await gatewayApi.transaction.getStatus(
  'txid_rdx1...'  // intent hash from sendTransaction
)
// status.intent_status: "CommittedSuccess" | "CommittedFailure" | "Pending" | ...

Historical State

Query state at a specific point in time by passing at_ledger_state:

const historicalDetails = await gatewayApi.state.innerClient.stateEntityDetails({
  stateEntityDetailsRequest: {
    addresses: ['account_rdx1...']
    at_ledger_state: { state_version: 12345678 }
  }
})

Maintenance Status (checked August 2026)

The SDK and the service it talks to are on different clocks, and it is worth knowing which is which. The client library has been at 1.10.1 since March 2025 — it is a generated client over a stable API, so age here mostly means the API has not changed underneath it. The Gateway service is more recent but also slowing: release v1.10.6 on 7 April 2026, and a final documentation-only commit on 20 May 2026. As of 7 August 2026 the Gateway is maintained on a volunteer basis with bug fixes only, alongside the dApp Toolkit and the Radix Wallet.

The practical consequence is about hosting rather than code. The public Gateway this SDK defaults to is Foundation-operated infrastructure now in maintenance mode, and it sits at the top of the Accountability Council's inventory of services a community DAO would need to take over. If your dApp cannot tolerate that dependency, run your own Gateway or use a third-party provider — see Radix APIs.

Next Steps

• ROLA Authentication – prove server-side that a user really controls the account they claim

External Links

• @radixdlt/babylon-gateway-api-sdk on npm
• Gateway API reference
• Mainnet Gateway Swagger UI