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rail API Specification (1.1.2)

Welcome to the rail Developer Guide!

Download OpenAPI description
rail-spec.json
rail-spec.yaml
Languages
Servers
Mock server

https://docs.rail.io/_mock/api-docs/openapi/rail-spec/

Sandbox - Stable API Instance

https://sandbox.layer2financial.com/api/

Production - Stable API Instance

https://platform.layer2financial.com/api/

Applications

Applications represent the onboarding journey for your customers. They are used to collect KYC information and documents required to open accounts on the platform. Visit our guides for a detailed understanding on how to use these APIs.

Operations

Accounts

Accounts are used to hold funds on the platform. Once a customer is onboarded via the application process, you can create accounts for them in various currencies.

Operations

Counterparties

Counterparties represent external entities that you may wish to send or receive funds from. All counterparties are verified to ensure compliance with regulatory requirements prior to being available for use for withdrawals.

Operations

Customers

Customers can only be created via the application process. Once created, customers can have multiple accounts associated with them.

Operations

Deposits

Deposits are used to request instructions for funding platform managed accounts from external sources. A given account may have many deposits associated with it depending on the supported rails and configurations.

Operations

Documents

Document uploading and management functions.

Operations

Exchanges

Exchanges are used to convert funds from one currency to another. This is achieved by moving money between 2 platform accounts that are denominated in different currencies. We have eliminated the complexity of traditional currency trading.

Operations

Payments

Payments are used to orchestrate end to end payment flows from external parties or from within the platform.

Operations

Transactions

Transactions are created to record the movement of funds between accounts. The transactions endpoint allows the bulk retrieval of transaction data for reconciliation and reporting purposes.

Operations

Transfers

Transfer are used to move funds between two platform managed accounts that are denominated in the same currency.

Operations

Create Transfer

Request

Request a new transfer. The transfer must be accepted prior to executing

Security
OAuth2Flow
Headers
Authorizationstring

OAuth bearer token (see authentication flows)

x-l2f-request-idstring

Optional Unique ID per request, useful for fault resolution/diagnosis and audit.

x-l2f-idempotency-idstring

Unique ID used to safely retry an operation. See idempotency section for more details.

Bodyapplication/jsonrequired
source_account_idstringrequired

Source account from which funds will be withdrawn

destination_account_idstringrequired

Destination account where funds will be deposited

amountnumberrequired

Amount to transfer from the source account to the destination account

descriptionstring

(Optional) Description of the transfer

curl -i -X POST \
  https://docs.rail.io/_mock/api-docs/openapi/rail-spec/v1/transfers \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>' \
  -H 'Content-Type: application/json' \
  -H 'x-l2f-idempotency-id: string' \
  -H 'x-l2f-request-id: string' \
  -d '{
    "source_account_id": "string",
    "destination_account_id": "string",
    "amount": 0,
    "description": "string"
  }'

Responses

Success

Bodyapplication/json
dataobject(Transfer)required
data.​idstringread-onlyrequired

Unique ID of the transfer request, to be used to accept the transfer and lookup status

data.​statusstringread-onlyrequired

Status of the transfer. Cannot be modified directly by the client.

  • REQUESTED - Transfer request is created and has passed validation. It must be accepted at which point it will be executed.
  • ACCEPTED - Transfer request has been accepted and is waiting execution. At this point it cannot be cancelled.
  • EXPIRED - Occurs when a transfer request was not accepted within a reasonable time frame. The transfer cannot be replayed from this state.
  • CANCELLED - Transfer request was cancelled. Only available prior to acceptance. The transfer request cannot be replayed from this state.
  • EXECUTED - Transfer request has been executed, it is completed with all ledger entries performed.
  • REJECTED - Transfer request was rejected and cannot be executed.
Enum"REQUESTED""ACCEPTED""EXPIRED""CANCELLED""EXECUTED""REJECTED"
data.​created_timestampstring(date-time)read-onlyrequired

Time when the transfer request was generated

data.​valid_untilstring(date-time)read-onlyrequired

Time when this transfer request expires and can no longer be accepted. Upon expiry a new transfer must be requested

data.​source_detailsobject(TransferSourceAccount)required

Details of transaction to be performed on the source account on acceptance

data.​source_details.​source_account_idstringrequired

Source account ID

data.​source_details.​asset_type_idstring

Asset type IDs follow a simple structure as follows: {$BLOCKCHAIN}_{$NETWORK}_{$CURRENCY_CODE} Simple asset type to test with include.

  • ETHEREUM_SEPOLIA_ETH
  • ETHEREUM_SEPOLIA_USDC
  • SOLANA_DEVNET_SOL
  • BITCOIN_TESTNET_BTC
  • FIAT_TESTNET_USD
  • FIAT_TESTNET_USD
  • FIAT_MAINNET_USD
  • FIAT_TESTNET_EUR
data.​source_details.​amount_to_debitnumberrequired

Amount that will be debited from the source account

data.​destination_detailsobject(TransferDestinationAccount)required

Details of transaction to be performed on the destination account on acceptance

data.​destination_details.​destination_account_idstringrequired

Destination account ID

data.​destination_details.​asset_type_idstring

Asset type IDs follow a simple structure as follows: {$BLOCKCHAIN}_{$NETWORK}_{$CURRENCY_CODE} Simple asset type to test with include

  • ETHEREUM_SEPOLIA_ETH
  • ETHEREUM_SEPOLIA_USDC
  • SOLANA_DEVNET_SOL
  • BITCOIN_TESTNET_BTC
  • FIAT_TESTNET_USD
  • FIAT_TESTNET_USD
  • FIAT_MAINNET_USD
  • FIAT_TESTNET_EUR
data.​destination_details.​amount_to_creditnumberrequired

Amount that will be credited to the destination account

Response
application/json
{
  "data": {
    "id": "string",
    "status": "REQUESTED",
    "created_timestamp": "2019-08-24T14:15:22Z",
    "valid_until": "2019-08-24T14:15:22Z",
    "source_details": { … },
    "destination_details": { … }
  }
}

Accept Transfer

Request

Accept a requested transfer. This will execute the transfer and may not be reversible depending on the owner of the destination account

Security
OAuth2Flow
Path
idstringrequired

Transfer ID

Headers
Authorizationstring

OAuth bearer token (see authentication flows)

x-l2f-request-idstring

Optional Unique ID per request, useful for fault resolution/diagnosis and audit.

x-l2f-idempotency-idstring

Unique ID used to safely retry an operation. See idempotency section for more details.

x-signaturestring

Client signature to validate the provence of the API request. See signing section for more details.

x-timestampstring

Current timestamp, represented AS unix epoch seconds. Mandatory when x-signature is provided.

curl -i -X POST \
  'https://docs.rail.io/_mock/api-docs/openapi/rail-spec/v1/transfers/{transfer_id}/accept' \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>' \
  -H 'x-l2f-idempotency-id: string' \
  -H 'x-l2f-request-id: string' \
  -H 'x-signature: string' \
  -H 'x-timestamp: string'

Responses

Success

Bodyapplication/json
dataobject(TransferBase)required
data.​idstringread-onlyrequired

Unique ID of the transfer request, to be used to accept the transfer and lookup status

data.​statusstringread-onlyrequired

Status of the transfer. Cannot be modified directly by the client.

  • REQUESTED - Transfer request is created and has passed validation. It must be accepted at which point it will be executed.
  • ACCEPTED - Transfer request has been accepted and is waiting execution. At this point it cannot be cancelled.
  • EXPIRED - Occurs when a transfer request was not accepted within a reasonable time frame. The transfer cannot be replayed from this state.
  • CANCELLED - Transfer request was cancelled. Only available prior to acceptance. The transfer request cannot be replayed from this state.
  • EXECUTED - Transfer request has been executed, it is completed with all ledger entries performed.
  • REJECTED - Transfer request was rejected and cannot be executed.
Enum"REQUESTED""ACCEPTED""EXPIRED""CANCELLED""EXECUTED""REJECTED"
Response
application/json
{
  "data": {
    "id": "string",
    "status": "REQUESTED"
  }
}

Retrieve Transfer

Request

Retrieves details of a previously requested transfer

Security
OAuth2Flow
Path
idstringrequired

Transfer ID

Headers
Authorizationstring

OAuth bearer token (see authentication flows)

x-l2f-request-idstring

Optional Unique ID per request, useful for fault resolution/diagnosis and audit.

curl -i -X GET \
  'https://docs.rail.io/_mock/api-docs/openapi/rail-spec/v1/transfers/{transfer_id}' \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>' \
  -H 'x-l2f-request-id: string'

Responses

Success

Bodyapplication/json
dataobject(Transfer)required
data.​idstringread-onlyrequired

Unique ID of the transfer request, to be used to accept the transfer and lookup status

data.​statusstringread-onlyrequired

Status of the transfer. Cannot be modified directly by the client.

  • REQUESTED - Transfer request is created and has passed validation. It must be accepted at which point it will be executed.
  • ACCEPTED - Transfer request has been accepted and is waiting execution. At this point it cannot be cancelled.
  • EXPIRED - Occurs when a transfer request was not accepted within a reasonable time frame. The transfer cannot be replayed from this state.
  • CANCELLED - Transfer request was cancelled. Only available prior to acceptance. The transfer request cannot be replayed from this state.
  • EXECUTED - Transfer request has been executed, it is completed with all ledger entries performed.
  • REJECTED - Transfer request was rejected and cannot be executed.
Enum"REQUESTED""ACCEPTED""EXPIRED""CANCELLED""EXECUTED""REJECTED"
data.​created_timestampstring(date-time)read-onlyrequired

Time when the transfer request was generated

data.​valid_untilstring(date-time)read-onlyrequired

Time when this transfer request expires and can no longer be accepted. Upon expiry a new transfer must be requested

data.​source_detailsobject(TransferSourceAccount)required

Details of transaction to be performed on the source account on acceptance

data.​source_details.​source_account_idstringrequired

Source account ID

data.​source_details.​asset_type_idstring

Asset type IDs follow a simple structure as follows: {$BLOCKCHAIN}_{$NETWORK}_{$CURRENCY_CODE} Simple asset type to test with include.

  • ETHEREUM_SEPOLIA_ETH
  • ETHEREUM_SEPOLIA_USDC
  • SOLANA_DEVNET_SOL
  • BITCOIN_TESTNET_BTC
  • FIAT_TESTNET_USD
  • FIAT_TESTNET_USD
  • FIAT_MAINNET_USD
  • FIAT_TESTNET_EUR
data.​source_details.​amount_to_debitnumberrequired

Amount that will be debited from the source account

data.​destination_detailsobject(TransferDestinationAccount)required

Details of transaction to be performed on the destination account on acceptance

data.​destination_details.​destination_account_idstringrequired

Destination account ID

data.​destination_details.​asset_type_idstring

Asset type IDs follow a simple structure as follows: {$BLOCKCHAIN}_{$NETWORK}_{$CURRENCY_CODE} Simple asset type to test with include

  • ETHEREUM_SEPOLIA_ETH
  • ETHEREUM_SEPOLIA_USDC
  • SOLANA_DEVNET_SOL
  • BITCOIN_TESTNET_BTC
  • FIAT_TESTNET_USD
  • FIAT_TESTNET_USD
  • FIAT_MAINNET_USD
  • FIAT_TESTNET_EUR
data.​destination_details.​amount_to_creditnumberrequired

Amount that will be credited to the destination account

Response
application/json
{
  "data": {
    "id": "string",
    "status": "REQUESTED",
    "created_timestamp": "2019-08-24T14:15:22Z",
    "valid_until": "2019-08-24T14:15:22Z",
    "source_details": { … },
    "destination_details": { … }
  }
}

Withdrawals

Move funds from a platform managed account to an external counterparty via supported rails.

Operations

Settlements

Settlement services for funds confirmation and reconciliation. Settlements are a deprecated concept and will be removed in future versions of the API. Please use Payments for all new integrations.

Operations

Subscriptions (Webhooks)

Manage your callback (webhook) subscriptions. Subscriptions allow you to receive real-time notifications of events that occur within your platform instance. Visit the guides for a full breakdown of all available events.

Operations
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