No-Backend AI Payment Automation Pipeline

An automated pipeline routing Stripe, PayPal, and Mobile Money (MoMo) transactions using Make.com, Gemini, and Google Sheets.

Author
Affiliation

Mbiarrambang Alain

PaveWay Academy

Published

August 29, 2026

This guide provides a comprehensive blueprint for building a scalable, completely serverless payment verification and logging infrastructure. The system leverages automated API webhooks for card payments alongside an AI agent to clean, parse, and flag manual Mobile Money transactions.

1 System Architecture

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flowchart TD
    Start([Landing Page Form Submission]) -->|Webhook| Router{Make / Zapier Router}
    
    Router -->|Path A| CC[Stripe Checkout]
    Router -->|Path B| PP[PayPal Smart Button]
    Router -->|Path C| MoMo[Manual MoMo ID Input]

    CC -->|checkout.session.completed| Ledger[(Google Sheets Ledger)]
    PP -->|Instant Payment Notification| Ledger
    
    MoMo --> Gemini[Gemini API gpt-4o-mini]
    Gemini -->|Structured JSON Format| Ledger

    Ledger --> StatusCheck{Row Status?}
    StatusCheck -->|Paid| Deliver[Auto-Deliver Product via Postmark/Mailgun]
    StatusCheck -->|Pending Verification| Alert[Slack/Telegram Admin Alert]
    
    Alert --> Manual[Manual Ledger Check]
    Manual -->|1-Click Approval Webhook| Approve[Update Row Status to Paid]
    Approve --> Deliver

2 Step-by-Step Implementation Guide

2.1 Step 1: Capture Front-End Ingestion Data

2.1.1 Infrastructure Selection

Utilize form frameworks that support logic-routing and native webhook outputs (e.g., Tally.so, Typeform, or embedded Framer Forms).

2.1.2 Form Configuration Properties

Configure fields strictly adhering to the following structure:

  • customer_name (Text)
  • customer_email (Email, Required)
  • product_tier (Dropdown/Radio)
  • payment_method (Dropdown: Stripe, PayPal, Mobile Money)
  • momo_transaction_id (Conditional Text Field: Visible only if payment_method equals Mobile Money).

2.1.3 The Ingestion Trigger

Set up a POST Request webhook mechanism on your form builder. Route the JSON payload directly to a custom webhook URL generated inside your Make.com or Zapier automation scenario.

2.2 Step 2: Establish the Routing Logic

Add a Router Module directly after your webhook listener inside Make.com to orchestrate workflow splitting:

2.2.1 Path A: Credit Card / Standard (Stripe)

Generate and serve a hosted Stripe Checkout Link. Pause execution down this path until Stripe shoots a checkout.session.completed event to your handler.

2.2.2 Path B: Digital Wallet (PayPal)

Deploy a PayPal smart button on your site. Configure the automation to wait for an Instant Payment Notification (IPN) webhook payload matching the customer’s email.

2.2.3 Path C: Mobile Money Manual Settlement (MoMo)

When a customer inputs an arbitrary manual receipt ID string, immediately catch the payload and route it straight to the Gemini integration module.

2.3 Step 3: Implement AI Structuring & Data Validation

Manual inputs introduce high error margins (copy-paste truncated digits, localized telecom prefixes, or malicious fraud strings). You must sanitize this data before logging it.

2.3.1 Module Configuration

  • Model: gemini-3.5-flash
  • Response Format: json_object

2.3.2 System Prompt Configuration

You are a specialized financial operations parser. Analyze the following user-submitted Mobile Money (MoMo) transaction text payload.

[USER SUBMISSION]: "{{Step1.momo_transaction_id}}"

Tasks:
1. Isolate and extract the alphanumeric transaction ID. Remove spaces, dashes, or extraneous terms (e.g., "ID:", "TXN", "Ref").
2. Validate if the string profile aligns with standard network structures (e.g., MTN MoMo typically matches 10-11 digits or specific alphanumeric profiles, Orange Money uses unique string lengths).
3. Guess the carrier network based on known structural footprints.

Output a strictly valid JSON object complying with this schema:
{
  "is_valid_format": boolean,
  "cleaned_id": "string",
  "carrier_guess": "string"
}

2.4 Step 4: Populate the Visual Database Ledger

Create a Google Sheet (or Airtable Base) to perform the role of your system ledger. Map properties meticulously to chronological rows:

Column Name Value Source Data Type Notes
Timestamp {now} DateTime System date
Customer Email Form Submission String Primary identity key
Payment Method Form Submission String Stripe / PayPal / MoMo
Raw Input ID Form Submission String Preserved for auditing
Cleaned ID Gemini Output String Evaluated string
Status Conditional Router String Paid (Stripe/PayPal) OR Pending Verification (MoMo)

2.5 Step 5: Configure Notifications and Product Delivery

graph TD
    A[Log Row in Google Sheets] --> B{Check Status}
    B -- Paid --> C[Trigger Postmark/Mailgun API]
    C --> D[Instantly Deliver Product Link]
    B -- Pending Verification --> E[Webhook to Slack/Telegram]
    E --> F[Admin Checks Phone Ledger]
    F --> G[Click 'Approve' Button via Webhook]
    G --> H[Update Sheet to Paid & Send Product]

2.5.1 Automatic Delivery Path (Paid)

If Status evaluates directly to Paid, route downstream directly to a Mailgun or Postmark module to fire out transactional product assets.

2.5.2 Human-in-the-Loop Verification Path (Pending Verification)

  1. Create a notification module targeting an internal Slack or Telegram endpoint.

  2. Structure the alert payload clearly: > ⚠️ New Manual MoMo Payment Verification Required > * User: {Email} > * Declared ID: {Cleaned_ID} > * Inferred Carrier: {Carrier_Guess} > >

  3. Append an active interactive webhook button in the notification labeled “Approve Transaction”.

  4. Clicking this button sends a payload back to a secondary execution hook in Make.com, which targets the corresponding Google Sheet row, shifts Status to Paid, and releases the delivery email.

3 Technology Stack Matrix

Component Recommended Tool Core Architectural Justification
Automation Engine Make.com Substantially more cost-efficient handling of data routers, conditional filters, and loops than Zapier.
Payment Gateways Stripe & PayPal Eliminates custom endpoints; offloads security and hosting directly to secure payment pages.
AI Parsing Layer Gemini API (gpt-4o-mini) Fast inference speeds, exceptionally cheap unit economics for token passing, supports absolute structural JSON integrity.
No-Code Database Google Sheets / Airtable Easily interfaces with modern integrations; simplifies visual inspection for support and operations teams.

4 Operational Risk Management

WarningMoMo Fraud Matrix

Because users can key in fictitious sequences to attempt access, never automate automatic fulfillment for manual Mobile Money strings. Retain strict structural boundary blocks: keep them pinned at Pending Verification until an operator manually checks their physical phone ledger balance.

NoteWebhook Queueing & Fault Tolerance

Network latency or transient upstream API lockouts can kill webhooks. Ensure that Queueing / Advanced Error Handling is checked inside Make.com settings. This saves failed data points into a dead-letter queue rather than dropping customer contexts completely.

ImportantCompliance Note

Ensure your landing page terms of service communicate that payment references are safely processed via encrypted third-party validation layers to conform with localized consumer privacy frameworks.