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/Merchant Initiated

Commerce API (2.0)

The Hellgate Commerce API provides a comprehensive payment orchestration platform designed to streamline and optimize payment processing for modern businesses. Built with flexibility and security at its core, our API enables you to process payments, manage authentications, and handle cardholder data across multiple payment processors without vendor lock-in.

Operating Models

Hellgate Commerce supports four distinct operating models to match your business needs:

  1. Primary Merchant - The standard operating model. Works great for single merchant setups.
  2. Platform - An operating model, which allows to process platform / marketplace payments.
  3. Ecosystem - An operationg model based on network tokens, which allows to facilitate transactions in e-commerce ecosystems.
  4. Managed Ecosystem - In this operating model, the management of the ecosystem is provided by Starfish as a service.

API Organization

The API is organized into logical groups:

  • Payments: Process and manage payment transactions
  • Authentications: Handle 3-D Secure authentication flows
  • Tokens: Create and manage payment tokens with network token support
  • Configuration: Manage merchants and account settings
  • Automation: Import existing tokens and generate reconciliation reports
Download OpenAPI description
openapi.json
openapi.yaml
Overview
URL

https://hellgate.io

Starfish GmbH & Co. KG

hello@starfish.team

License

Hellgate API Terms

Languages
Servers
Hellgate Sandbox

https://sandbox.hellgate.io/

Hellgate Production

https://api.hellgate.io/

Customer Initiated

These endpoints handle payment processing where the customer is actively present and authorizing the transaction.

Supports multiple payment scenarios:

  • One-off payments: Single transactions for immediate purchase
  • Initial recurring: First payment in a subscription series with customer consent
  • Initial unscheduled: First payment for card-on-file scenarios

All customer-initiated payments optionally support 3-D Secure authentication for enhanced security.

Operations

Merchant Initiated

These transactions occur without direct customer interaction at the time of payment.

Key use cases:

  • Recurring subscriptions: Automated billing for subscription services
  • Unscheduled transactions: Variable charges based on usage or consumption
  • Retry logic: Re-attempt failed payments with stored credentials

All merchant-initiated payments must reference a prior customer-initiated transaction for compliance.

Operations

Unscheduled

Request

Request a subsequent unscheduled payment.

  • The customer does not need to be on-session for this payment.
  • If 3RI is enabled on the account, the payment request can include an off-session authentication initiated by the requestor.
Security
APIKeyAuth
Path
idstring(uuid)required

The ID of the initial payment

Bodyapplication/json
additional_informationobject
amountinteger>= 0required

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

currency_codestringrequired

The three letter currency code. See: ISO-4217

authentication_preferencestring

The preference for the authentication method to be used for the payment.

Preference Description
NO_3RIDon't perform 3RI authentication for this payment (Default).
TRY_3RITry to perform 3RI authentication for this payment. If it fails the payment will still be sent for authorization.
REQUIRE_3RIRequire 3RI authentication for this payment. If it fails the payment will not be sent for authorization.
Default "NO_3RI"
Enum"NO_3RI""TRY_3RI""REQUIRE_3RI"
referencestring<= 80 charactersrequired

A description of the payment for later reference

metadataobject

Metadata consisting of entries, each of which each includes a key and an associated value:

  • Maximum 20 key-value pairs.
  • Maximum 20 characters per key.
  • Maximum 80 characters per value.
Example: {"my_key_one":"my_value_one","my_key_two":"my_value_two"}
curl -i -X POST \
  'https://sandbox.hellgate.io/payments/unscheduled/{id}/subsequent' \
  -H 'Content-Type: application/json' \
  -H 'X-API-Key: YOUR_API_KEY_HERE' \
  -d '{
    "amount": 1000,
    "currency_code": "EUR",
    "authentication_preference": "NO_3RI",
    "reference": "Order #12345"
  }'

Responses

Success response

Bodyapplication/json
idstring(uuid)required

The ID of the payment on Hellgate

action_requirementobject
additional_informationobject
authentication_preferencestring

The preference for the authentication method to be used for the payment.

Preference Description
NO_3RIDon't perform 3RI authentication for this payment (Default).
TRY_3RITry to perform 3RI authentication for this payment. If it fails the payment will still be sent for authorization.
REQUIRE_3RIRequire 3RI authentication for this payment. If it fails the payment will not be sent for authorization.
Default "NO_3RI"
Enum"NO_3RI""TRY_3RI""REQUIRE_3RI"
authentication_resultobject

The final result of the authentication. It holds in the cardholder authentication data (CAVV) and if there is a network token present, the token authentication data (TAVV).

amountobjectrequired
amount.​requestedinteger>= 0

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

amount.​authorizedinteger>= 0

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

amount.​capturedinteger>= 0

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

amount.​voidedinteger>= 0

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

amount.​refundedinteger>= 0

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

created_atstring(date-time)required

The date-time the payment was created (following ISO 8601)

currency_codestringrequired

The three letter currency code. See: ISO-4217

credential_idstring(uuid)

The ID of the credential associated with the payment.

failure_detailsArray of objects

The reasons why a payment failed during processing in Hellgate.

This can be due to processing errors on the side of the processor, as well as errors in the processing of the underlying flow.

In case the failure is due to a processing problem, the transaction history of the payment can give more information on the exact failure details.

flow_matrix_rulestring

The rule in the flow matrix, which was chosen to process the payment.

initial_payment_idstring(uuid)

The ID of the initial payment.

Only present for subsequent merchant-initiated payments.

processing_annotationsobject

This is an optional attribute holding results from eventual pre-processing of the request.

referencestring<= 80 charactersrequired

A description of the payment for later reference

recurring_expirystring(yyyyMMdd)

The date when the recurring should expiry.

Only present for recurring payments.

recurring_frequencyinteger

Indicates the minimum number of days between authorisations.

Only present for recurring payments.

sourceany

The source that was used for the payment.

TypeDescription
cardThe payment method card was used as source
splitsArray of objectsnon-empty

An array of split instructions.

Data in this array is only processed on a Hellgate account in the platform operating model. If you are in doubt, please reach out to your account representative.

TypeDescription
sellerSending the given amount to the seller referenced by the merchant_id in the payload. The seller needs to be onboarded to the account and linked to the processor in order to receive funds from a payment split.
commissionAn already existing Hellgate token can be used as source for the payment.
statusstringrequired
Enum"open""processing""failed""authorized""capturing""captured""settling""settled""voiding""voided"
use_casestringrequired

Definition of the payment use-case for processing

Enum"ONE_OFF""UNSCHEDULED""SUBSEQUENT_UNSCHEDULED""RECURRING""SUBSEQUENT_RECURRING"
metadataobject

Metadata consisting of entries, each of which each includes a key and an associated value:

  • Maximum 20 key-value pairs.
  • Maximum 20 characters per key.
  • Maximum 80 characters per value.
Example: {"my_key_one":"my_value_one","my_key_two":"my_value_two"}
Response
application/json
{
  "id": "54ba1fdb-7e4e-402b-aebb-66f9d5345cf8",
  "amount": {
    "requested": 1000
  },
  "authentication_preference": "NO_3RI",
  "created_at": "2023-10-10T00:00:00Z",
  "currency_code": "EUR",
  "credential_id": "7d542f79-5f16-44e1-8fff-e8cbaf2597f9",
  "initial_payment_id": "2c973d90-751e-4e66-a6bf-c53a9a56f93e",
  "reference": "Order #12345",
  "source": {
    "type": "card",
    "cardholder_name": "Bob Holder",
    "expiry_month": 12,
    "expiry_year": 2030,
    "masked_account_number": "424242XXXXXX4242",
    "pan_type": "FPAN"
  },
  "status": "processing",
  "use_case": "SUBSEQUENT_UNSCHEDULED"
}

Callbacks

Payment Notification callback
post

Recurring

Request

Request a subsequent recurring payment.

  • The customer does not need to be on-session for this payment.
  • If 3RI is enabled on the account, the payment request can include an off-session authentication initiated by the requestor.

The request must to follow the schedule defined by the initial recurring payment.

Security
APIKeyAuth
Path
idstring(uuid)required

The ID of the initial payment

Bodyapplication/json
additional_informationobject
amountinteger>= 0required

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

currency_codestringrequired

The three letter currency code. See: ISO-4217

authentication_preferencestring

The preference for the authentication method to be used for the payment.

Preference Description
NO_3RIDon't perform 3RI authentication for this payment (Default).
TRY_3RITry to perform 3RI authentication for this payment. If it fails the payment will still be sent for authorization.
REQUIRE_3RIRequire 3RI authentication for this payment. If it fails the payment will not be sent for authorization.
Default "NO_3RI"
Enum"NO_3RI""TRY_3RI""REQUIRE_3RI"
referencestring<= 80 charactersrequired

A description of the payment for later reference

metadataobject

Metadata consisting of entries, each of which each includes a key and an associated value:

  • Maximum 20 key-value pairs.
  • Maximum 20 characters per key.
  • Maximum 80 characters per value.
Example: {"my_key_one":"my_value_one","my_key_two":"my_value_two"}
curl -i -X POST \
  'https://sandbox.hellgate.io/payments/recurring/{id}/subsequent' \
  -H 'Content-Type: application/json' \
  -H 'X-API-Key: YOUR_API_KEY_HERE' \
  -d '{
    "amount": 1000,
    "currency_code": "EUR",
    "authentication_preference": "NO_3RI",
    "reference": "Order #12345"
  }'

Responses

Success response

Bodyapplication/json
idstring(uuid)required

The ID of the payment on Hellgate

action_requirementobject
additional_informationobject
authentication_preferencestring

The preference for the authentication method to be used for the payment.

Preference Description
NO_3RIDon't perform 3RI authentication for this payment (Default).
TRY_3RITry to perform 3RI authentication for this payment. If it fails the payment will still be sent for authorization.
REQUIRE_3RIRequire 3RI authentication for this payment. If it fails the payment will not be sent for authorization.
Default "NO_3RI"
Enum"NO_3RI""TRY_3RI""REQUIRE_3RI"
authentication_resultobject

The final result of the authentication. It holds in the cardholder authentication data (CAVV) and if there is a network token present, the token authentication data (TAVV).

amountobjectrequired
amount.​requestedinteger>= 0

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

amount.​authorizedinteger>= 0

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

amount.​capturedinteger>= 0

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

amount.​voidedinteger>= 0

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

amount.​refundedinteger>= 0

The amount given in minor units (e.g. use 700 for 7€). Some currencies do not support minor units (e.g. Japanese Yen). In this case send in the full value, .i.e. 100 for 100 JPY.

created_atstring(date-time)required

The date-time the payment was created (following ISO 8601)

currency_codestringrequired

The three letter currency code. See: ISO-4217

credential_idstring(uuid)

The ID of the credential associated with the payment.

failure_detailsArray of objects

The reasons why a payment failed during processing in Hellgate.

This can be due to processing errors on the side of the processor, as well as errors in the processing of the underlying flow.

In case the failure is due to a processing problem, the transaction history of the payment can give more information on the exact failure details.

flow_matrix_rulestring

The rule in the flow matrix, which was chosen to process the payment.

initial_payment_idstring(uuid)

The ID of the initial payment.

Only present for subsequent merchant-initiated payments.

processing_annotationsobject

This is an optional attribute holding results from eventual pre-processing of the request.

referencestring<= 80 charactersrequired

A description of the payment for later reference

recurring_expirystring(yyyyMMdd)

The date when the recurring should expiry.

Only present for recurring payments.

recurring_frequencyinteger

Indicates the minimum number of days between authorisations.

Only present for recurring payments.

sourceany

The source that was used for the payment.

TypeDescription
cardThe payment method card was used as source
splitsArray of objectsnon-empty

An array of split instructions.

Data in this array is only processed on a Hellgate account in the platform operating model. If you are in doubt, please reach out to your account representative.

TypeDescription
sellerSending the given amount to the seller referenced by the merchant_id in the payload. The seller needs to be onboarded to the account and linked to the processor in order to receive funds from a payment split.
commissionAn already existing Hellgate token can be used as source for the payment.
statusstringrequired
Enum"open""processing""failed""authorized""capturing""captured""settling""settled""voiding""voided"
use_casestringrequired

Definition of the payment use-case for processing

Enum"ONE_OFF""UNSCHEDULED""SUBSEQUENT_UNSCHEDULED""RECURRING""SUBSEQUENT_RECURRING"
metadataobject

Metadata consisting of entries, each of which each includes a key and an associated value:

  • Maximum 20 key-value pairs.
  • Maximum 20 characters per key.
  • Maximum 80 characters per value.
Example: {"my_key_one":"my_value_one","my_key_two":"my_value_two"}
Response
application/json
{
  "id": "54ba1fdb-7e4e-402b-aebb-66f9d5345cf8",
  "amount": {
    "requested": 1000
  },
  "authentication_preference": "NO_3RI",
  "created_at": "2023-10-10T00:00:00Z",
  "currency_code": "EUR",
  "credential_id": "7d542f79-5f16-44e1-8fff-e8cbaf2597f9",
  "initial_payment_id": "2c973d90-751e-4e66-a6bf-c53a9a56f93e",
  "reference": "Order #12345",
  "source": {
    "type": "card",
    "cardholder_name": "Bob Holder",
    "expiry_month": 12,
    "expiry_year": 2030,
    "masked_account_number": "424242XXXXXX4242",
    "pan_type": "FPAN"
  },
  "status": "processing",
  "use_case": "SUBSEQUENT_RECURRING"
}

Callbacks

Payment Notification callback
post

Payment Modifications

Modify existing payment transactions after initial authorization. Essential for flexible payment management across all operating models.

Available modifications:

  • Capture: Finalize pre-authorized payments (for two-step payment flows)
  • Void: Cancel authorized but uncaptured transactions
  • Refund: Return funds to customers for captured payments

Modifications can be applied across multiple processors, maintaining consistency in multi-processor setups.

Operations

Payment Data

Access comprehensive payment transaction data for reporting, reconciliation, and analysis. Critical for all operating models to maintain transaction visibility.

Features:

  • Transaction history: Full audit trail of payment lifecycle
  • Multi-processor visibility: Unified view across all connected processors
  • Real-time status: Current state of payments with processor responses
  • Filtering capabilities: Search and filter by multiple criteria
Operations

Refund Data

Access detailed refund transaction data for tracking and reconciliation. Essential for customer service and financial reporting across all operating models.

Provides:

  • Refund status tracking: Monitor refund processing across processors
  • Transaction linking: Connect refunds to original payments
  • Partial refund support: Track multiple refunds against single payments
  • Processor responses: Detailed feedback from payment processors
Operations

Customer Initiated

Hellgate allows to process EMVCo 3-D Secure authentication requests as standalone request.

For example, these endpoints can be used to process payment authentication centrally and process the subsequent authorization requests conditionally on different payment processors.

The secion of customer initiated authentications consists of three use-cases:

Use-Case Description
One OffA standard situation in which a single payment amount shall undergo 3-D Secure authentication.
Initial RecurringAn authentication of the first payment in the sequence of recurring payments.
Initial InstallmentAn authentication of the first payment in the sequence of installment payments.
Operations

Merchant Initiated (3RI)

Hellgate supports requestor-initiated EMVCo 3-D Secure authentication requests as standalone transactions.

All requests in this section must be linked to a prior customer-initiated authentication.

Operations

Authentication Data

Access the results of prior authentications for reference.

Operations

Credentials on File

Manage stored payment credentials for repeat customers across all operating models. Essential for subscription services, marketplaces, and ecosystems requiring seamless repeat transactions.

Capabilities:

  • Credential storage: Securely store customer payment methods for future use
  • Cross-processor portability: Use stored credentials with any connected processor
  • Compliance management: Automatic handling of card scheme mandates
  • Customer control: Enable customers to view and manage their stored payment methods
Operations

Create Hellgate Tokens

Hellgate Tokens are powerful instrument to manage card holder data in a PCI/DSS compliant way.

Compliance as a Service

Achieve PCI / DSS compliance in almost no time using our certified managed compliance service.

No Acquirer Lock-In

Transparently use the cardholder data across all connected processors to implement a non lock-in acquiring setup.

Network Tokens

For every card which is tokenized on Hellgate, network-tokens can be automatically provisioned. This allows for more secure transactions, better conversion, and ultimately lower processing cost.

Operations

Token Management

All cards stored with Hellgate can be managed via the endpoints in this section.

The CVC2 security code is only kept in an ephemeral cache for a few minutes. The API allows to manage this resource with these endpoints:

  • check if the CVC2 is still availble
  • request a new session to renew the CVC2 with our SDK
  • consume the token after a successful authorization on an external processor
Operations

Compliance Service

Safely handle sensitive cardholder data while maintaining PCI DSS compliance across all operating models. Our compliance service acts as a secure proxy between your systems and payment processors.

Key features:

  • PCI DSS Level 1 certified: Reduce your compliance scope significantly
  • Data forwarding: Securely transmit cardholder data to processors without touching your systems
  • Format preservation: Maintain data formats required by different processors
Operations

Network Tokens

Hellgate supports Network Tokens with major card schemes.

The lifecycle of network tokens is automatically managed. When activated a network token is automatically provisioned and maintained through its life-cycle.

The use of Network Tokens requires prior activation by your account manager.

Operations

Merchants

Configure and manage merchant accounts based on your chosen operating model. The merchant management capabilities adapt to support all four Hellgate Commerce operating models.

The default model for single businesses. Your account operates as a standalone merchant processing its own transactions.

  • Single merchant configuration locked to your primary account
  • Cannot add sub-merchants (POST /merchants disabled)
  • Cannot delete the primary merchant (DELETE /merchants/{id} disabled)
  • Full access to all payment features for your own transactions
Operations

Processor Backup

In case your precious payment-method data is currently locked into an acquirer processor, Hellgate allows you to migrate the tokens automatically. Currently we support stripe.com, but more processors are on our list. Please ask you account manager for more information.

Detailed documentation on how to migrate your stripe payment methods can be found on the Hellgate Developer Documentation.

Operations

Reconciliation

Reconcile imported token data.

Operations
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