ImliStack Start a project

API & Integration Engineering

Integrations that keep working after launch day

Payments, CRMs, search, messaging and accounting systems — we connect your product to the services it depends on, with webhooks, retries and reconciliation designed in from the start.

Discuss your project See entry engagements

What does reliable payment gateway integration involve?

Reliable payment integration means more than adding a checkout button. It includes server-side order creation, webhook-verified payment capture, idempotent handlers, refunds, payouts and reconciliation jobs that catch mismatches. ImliStack has integrated Stripe, Razorpay, Razorpay X payouts and HDFC SmartGateway, alongside Salesforce, Algolia, QuickBooks and Google APIs.

Is this for you

Where we usually help

If any of these sound familiar, a short call is the fastest way to find out whether we are the right fit.

  • Payments succeed at the gateway but orders stay unpaid in your system
  • Data is re-typed between your product, CRM and accounting tools
  • You need real-time chat, notifications or live status in your product
  • A partner or client needs a documented API to integrate with you

What we deliver

API & Integration Engineering capabilities

01

Payment gateways

Stripe, Razorpay and bank gateways with webhooks, refunds, payouts and reconciliation.

02

Webhooks & event processing

Signed, idempotent webhook handlers backed by queues (BullMQ, Bull, RabbitMQ).

03

CRM, search & accounting

Salesforce, Algolia, QuickBooks, Google Ads and Analytics data integrations.

04

Messaging & real-time

Socket.IO chat and live updates, email (SendGrid, Mailgun), SMS OTP and push (FCM).

05

Public & partner APIs

Versioned REST APIs with OAuth 2.0 or JWT, rate limits and OpenAPI/Swagger docs.

06

Auth & identity

OAuth 2.0, JWT, SSO and token revocation designed for multi-role products.

How we work

A delivery approach you can follow

Written plans, visible progress and decisions recorded as we go — so nothing depends on memory.

  1. Map the flows

    Document every state a payment, sync or message can be in — including failure.

  2. Design for failure

    Retries, idempotency keys, dead-letter queues and alerts before the happy path.

  3. Build & sandbox-test

    Exercise flows end to end in provider test modes and staging.

  4. Reconcile & monitor

    Scheduled checks and dashboards so mismatches are found by you, not customers.

Technology

Tools we use for api & integration engineering

We choose tools for your constraints, not our habits. See the full technology overview.

  • Stripe
  • Razorpay
  • Razorpay X
  • HDFC SmartGateway
  • Salesforce
  • Algolia
  • QuickBooks
  • Google APIs
  • Firebase FCM
  • SendGrid
  • Mailgun
  • Socket.IO
  • BullMQ
  • RabbitMQ
  • Swagger / OpenAPI

Proof, not promises

Wooziee runs Razorpay checkout and Razorpay X payouts in India and Stripe in its UK edition, with webhook-verified capture and reconciliation.

See the payment architecture

FAQ

API & Integration Engineering: common questions

Which payment gateways have you integrated?

Stripe, Razorpay (checkout and Razorpay X payouts) and HDFC SmartGateway, plus wallet and subscription flows. We are comfortable adding other gateways that provide documented APIs and sandboxes.

How do you prevent duplicate or missed payments?

Orders are created server-side, capture is confirmed by signed webhooks, handlers are idempotent, and a reconciliation job compares gateway records with your database on a schedule.

Can you build real-time chat into our product?

Yes. We build chat and live updates on WebSockets (Socket.IO) with authentication, message persistence and push notifications for offline users.

Related services

All services

Next step

Have a product to build or a system to fix?

Tell us what you are working on. You will get a considered reply from an engineer — with questions, a suggested approach or an honest “we are not the right fit”.

Start a project Book a discovery call