Backend and APIs

Backend and API engineering with production ownership

Cloudnonic designs, builds and runs backend systems and APIs for companies that need a platform other systems can depend on: partner integrations, multi-tenant products, regulated data. Senior engineers own the domain model, the API contracts, the security and the operations as one responsibility, in NestJS, FastAPI, Laravel or Rails on PostgreSQL and AWS. Done means the system is in production, monitored, and your team can change it.

GoMedicus public landing page with the online booking entry point and the list of services

What is included

Domain and data modelling

The entities, rules and permissions of your business written down and agreed before the first endpoint, so the API says what the business means.

API design and contracts

REST or GraphQL APIs with versioning, documented contracts, authentication and rate limits, designed for the partners and apps that will consume them.

Integrations

Connections to the systems your product depends on: payment, identity, booking channels, PIMs, devices, with retries, idempotency and monitoring on every boundary.

Security and compliance by design

Access control, audit trails, encryption and data residency built into the architecture, and documented for the enterprise and healthcare reviews that come later.

Operations

Automated pipelines with health checks and rollback, observability, backups that are restored in tests, and a named engineer on call.

Proof

Case studies in this scope. Every figure comes from the study behind it.

HealthTech — idea to Series A

GoMedicus

Months from kickoff workshop to Series A
19
Of the platform's engineering owned by Cloudnonic
100%
Measured recovery time in a disaster-recovery drill
47 min
Container deploy, with automatic rollback
8 min
  • NestJS
  • Next.js
  • PostgreSQL
  • AWS
  • Terraform
AI-Powered E-commerce Optimization

EKOM AI

Products monitored
50,000+
Uptime guarantee
99.9%
Teams trust the platform
20+
Support available
24/7
  • Python
  • React
  • AWS
  • Python
  • React
  • AWS
Industrial IoT — grid monitoring platform

IoT Energy

Field devices registered on the platform
366+
Transmission lines monitored
21+
Utilities and partners with their own tenant
13+
Sensor types with their own processing chain
5+
  • FastAPI
  • React
  • PostgreSQL
  • AWS Lambda
  • Terraform
Empowering Education & Community

START Campus

Years running the platform
5+
Ownership
100%
  • Laravel
  • React
  • Laravel
  • React
Next-Gen Learning Management

Elearnify

Organisations served
3,000+
Registered users
50,000+
Courses delivered
2,000+
  • Ruby on Rails
  • React Native
  • App Store
  • Google Play
Elearnify mobile app home screen for a learner: learning paths with video courses, durations and progress, in an organisation's blue themeElearnify mobile app home screen in a second organisation's purple theme, with onboarding learning paths and the offline downloads tab

How we work with you

How we work with you

Backend work runs as a product team when we own the whole platform, or as an embedded team inside your engineering organisation when you already have one. In both cases the engineers who scope the system are the ones who run it, which is how estimates stay honest and incidents stay rare.

Your product team · What this prevents: A prototype that never becomes a platform, and a CTO hire made before the product deserves one.

The two engagement models →

Stack we use

Chosen per project. We pick what your team can run after us, not what is fashionable.

  • NestJS
  • FastAPI
  • Laravel
  • Ruby on Rails
  • PostgreSQL
  • AWS
  • AWS
  • PostgreSQL
  • Ruby on Rails
  • Laravel
  • FastAPI
  • NestJS

What goes wrong, and what we decide instead

  1. An API shaped like the first screen

    Endpoints are added per feature, each returning what one page needs, and the second consumer, a partner or a mobile app, cannot use any of them.

    What it costs

    A rewrite of the API layer when the first integration is sold, usually under deadline.

    How we decide

    We model the domain first and design the contracts for the consumers you plan to have, with versioning from the start.

  2. Integrations without failure handling

    The payment provider times out, the partner API changes a field, and the system either double-books or silently drops the request.

    What it costs

    Reconciliation by hand, refunds, and a partner who stops trusting the integration.

    How we decide

    Every external boundary gets retries, idempotency keys, dead-letter handling and an alert, and we test the failure path before the happy path.

  3. Security added for the audit

    Audit trails, access rules and data residency are retrofitted when an enterprise customer or a regulator asks.

    What it costs

    A blocked deal while the platform is reworked, and findings that need architectural changes under pressure.

    How we decide

    Access control, audit logging and data residency are architecture decisions in the first weeks, documented so the review is a reading exercise.

Frequently asked questions

Which backend stack do you use?

NestJS on TypeScript and FastAPI on Python for new platforms, Laravel and Ruby on Rails where a client's system already runs on them, PostgreSQL as the default database and AWS as the default cloud. The choice is made per project, and we document why.

Do you take over an existing backend?

Yes, as an embedded team. We start with a review of the architecture, the deployment and the risks, agree what to stabilise first, and then work inside your repositories, standups and review process.

How do you keep the API stable for partners?

Documented contracts, versioning from the first release, backwards-compatible changes by default and a deprecation policy for the rest. Consumers are tested against the contract in the pipeline.

Who runs the system after launch?

We do, until your team can and wants to. Pipelines, monitoring, on-call and backups are part of the engagement, and everything is in your accounts and your repositories from day one, so there is no lock-in.

Built the AI-Native way

Every service on this page is delivered with our AI-Native process: specs as the source of truth, agents in the pipeline, and a named engineer signing off at staging.

How we build with AI →

Want to see how this would work for your product?

Book a call and we will go through your architecture, your constraints and what the first ninety days would look like.Book a technical consultation
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