SUBTC Protocol Integration with HostBill — Overview of Bitcoin Payment Gateway

## 1. Introduction

HostBill is a powerful billing and automation platform used for managing:
- VPS hosting
- Web hosting services
- Domain registration
- SaaS subscriptions

Integrating SUBTC Protocol turns HostBill into a **fully automated Bitcoin payment system** without relying on traditional payment processors.

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## 2. Integration Concept

SUBTC acts as the **payment execution layer**
HostBill acts as the **billing and service management layer**

Flow:

Client → HostBill Invoice → SUBTC API → Bitcoin Network → Payment Confirmation → Service Activation

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## 3. Core Integration Components

### 1. Custom Payment Gateway Module (HostBill)

A new gateway is created inside:

/includes/gateways/subtc/

Responsibilities:
- Generate BTC payment address per invoice
- Link invoice to SUBTC wallet/address
- Monitor payment status
- Automatically confirm payments

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### 2. SUBTC API Integration Layer

HostBill communicates with SUBTC using HTTP requests (curl / PHP cURL).

Main operations:
- wallet_create
- wallet_receive
- wallet_poll
- wallet_wait_event

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## 4. Payment Flow

### Step 1 — Invoice Creation

HostBill generates an invoice:
- invoice_id
- USD amount converted to satoshis

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### Step 2 — Generate Payment Address

$response = curl_post("https://api.subtc.net/v1/btc?mode=wallet_receive", [
  "wallet_id" => $wallet_id
]);

$address = $response["address"];

The address is displayed to the customer.

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Step 3 — Customer Payment

The user sends Bitcoin to the generated address.

HostBill stores:

address

expected_sat

invoice_id

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Step 4 — Payment Monitoring

Option 1: Polling

curl_post("https://api.subtc.net/v1/btc?mode=wallet_poll", [
  "wallet_id" => $wallet_id,
  "address" => $address,
  "expected_sat" => $amount_sat
]);

Option 2: Webhook (Recommended)

curl_post("https://api.subtc.net/v1/btc?mode=wallet_wait_event", [
  "wallet_id" => $wallet_id,
  "address" => $address,
  "expected_sat" => $amount_sat,
  "callback_url" => "https://yourhostbill.com/subtc-webhook"
]);

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Step 5 — Service Activation

When:

received_sat >= expected_sat

HostBill automatically:

Marks invoice as paid

Activates service (hosting/VPS/domain)

Sends confirmation to the client

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5. Webhook Handler Example

$data = json_decode(file_get_contents("php://input"), true);

if ($data["reached"] && $data["received_sat"] >= $data["expected_sat"]) {
    mark_invoice_paid($data["invoice_id"]);
    activate_service($data["service_id"]);
}

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6. Wallet Strategy

Recommended structure:

Hot Wallet (payment processing)

Operational Wallet (billing system funds)

Cold Wallet (secure storage)

Best practice:

Periodic withdrawal from hot wallet to cold storage

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7. Security Best Practices

Store API keys in .env

Use HTTPS for all webhook endpoints

Validate webhook payloads

Use idempotency keys to prevent double processing

Restrict gateway access by IP if possible

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8. Advantages of SUBTC + HostBill

No Bitcoin node required

No RPC complexity

Fully automated payments

Works on Mainnet & Testnet

AI-agent friendly architecture

Simple HTTP/cURL integration

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9. Use Cases

VPS hosting companies

Web hosting providers

Domain registrars

SaaS subscription services

Digital product platforms

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10. Conclusion

SUBTC transforms HostBill into a Bitcoin-native billing system.

HostBill = billing & automation layer
SUBTC = Bitcoin payment execution layer

Result:

→ Fully automated, API-driven Bitcoin hosting infrastructure.