NexusHand

Services

APIs that other developers thank you for

Clean REST APIs, sane versioning, real documentation — plus the integration work nobody enjoys: payment gateways, courier APIs, SMS, legacy systems.

Isometric illustration of a data store wired out to four connected endpoints

Fit

Who this is for

Products that need a real API

Mobile apps, partner integrations, or a public API customers will build on — designed to be understood without a meeting.

Businesses stitching systems together

Your store, courier, accounting, and SMS provider don't talk to each other. We build the connective tissue and own the failure cases.

Teams stuck with a fragile integration

The sync that silently fails, the webhook that double-fires. We make integrations observable, retryable, and boring.

Scope

What's included

REST API design & build

Predictable resources, consistent errors, pagination, and versioning from day one — an API developers thank you for.

Third-party integrations

Payment gateways (bKash, Nagad, SSLCommerz, Stripe), couriers (Pathao, Steadfast, Paperfly), SMS and email providers — integrated with retries and reconciliation, not just happy paths.

Webhooks & event delivery

Signed, idempotent, retried with backoff, and logged — so consumers can trust what you send.

Authentication & authorization

API keys, OAuth flows, JWT sessions, role scopes, and rate limiting appropriate to who's calling.

Documentation

OpenAPI specs and human-readable guides with copy-paste examples — docs a stranger can integrate from.

Legacy bridges

A clean modern API in front of the old system, so new products ship now while the legacy core retires gradually.

Observability

Structured logs, error alerting, and per-endpoint metrics — you'll know an integration broke before your customer does.

Approach

How we approach it

  1. 01

    Design the contract first

    We write the API spec before the code and review it with the people who'll consume it. Changing a document is cheap; changing production isn't.

  2. 02

    Assume every dependency fails

    Timeouts, retries, idempotency keys, and reconciliation jobs — because payment gateways and courier APIs do go down, usually at midnight.

  3. 03

    Version deliberately

    Breaking changes get a new version and a migration window. Your integrators' trust is worth more than a cleaner URL.

Logo strip of the payment gateways and courier services wired into qCommerz
Payments & couriers integrated in production

Tools

Stack we reach for

  • NestJS
  • Node.js
  • PostgreSQL
  • Redis
  • BullMQ
  • OpenAPI/Swagger

Queue-backed processing and typed contracts — the pattern our platforms use to move hundreds of thousands of orders.

Deliverables

What you get

  • An OpenAPI specification reviewed before build
  • Integration test suite covering failure modes, not just success
  • Signed, retried webhook delivery with a delivery log
  • Developer documentation with runnable examples
  • Monitoring and alerting on every critical endpoint

Proof

Our platforms integrate bKash, Nagad, SSLCommerz, Pathao, Steadfast, Paperfly, Telegram and SMS gateways — in production, under real order volume.

Frequently asked questions

Tell us what you're building

A 30-minute call is enough to tell you honestly whether we're the right team for it — and what it will take.

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