Backend API Development (FastAPI/Node)

Design and build robust backend APIs - secure, observable, and scalable services using FastAPI or Node.js, ready for cloud deployment and real-world operations.

Modern applications live or die on the quality of their APIs. Poorly designed backend services create downstream cost: brittle integrations, unclear contracts, security gaps, inconsistent error handling, and hard-to-support systems. As products scale, teams often discover that reliability, performance, and observability were never engineered in - leading to recurring incidents, slow delivery, and escalating technical debt.

LW IT Solutions delivers Backend API Development as a full lifecycle engineering service. We design clean API contracts, implement secure authentication and authorisation, build predictable validation and error handling, and integrate the data and systems you need - while ensuring the solution is testable and operationally supportable. We commonly deliver APIs using FastAPI (Python) or Node.js (JavaScript/TypeScript), and we can align delivery to your target platform (for example Azure App Service, Azure Container Apps, or Kubernetes) with CI/CD and observability patterns that match production expectations.

Talk through your requirements and leave with a clear next-step plan.

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Service Overview

Highlights

API design with OpenAPI contracts and clear versioning
FastAPI or Node.js delivery with secure authN and authZ patterns
Consistent validation and error handling for predictable client behaviour
Observability built in: structured logs, metrics, tracing, and health endpoints
Deployment and support readiness including CI/CD and runbook notes

Business Benefits

Stable API contracts that reduce rework for frontend and integration teams
Reduced security risk through consistent authentication, authorisation, and input validation
Improved reliability via predictable error handling, retries where appropriate, and clear operational behaviour
Faster delivery through automated testing and repeatable deployment pipelines
Better supportability with logging, metrics, health checks, and clear runbook guidance

Typical use cases

Backend services for web and mobile applications
APIs that expose line-of-business capabilities to internal teams or partners
Modernisation of legacy services into well-defined REST APIs
Integration services that connect databases, SaaS platforms, and internal systems
APIs that require improved reliability, monitoring, or security controls

Objectives & deliverables

What Success Looks Like

Create stable, well-documented API contracts that accelerate frontend and integration delivery
Implement secure authN/authZ aligned to your identity model
Build reliable integration with databases and third-party systems
Improve delivery velocity through automated testing and CI/CD pipelines
Reduce operational risk with logging, monitoring, and repeatable deployment patterns

What You Get

API specification (OpenAPI) and implementation aligned to your domain model
Secure authN/authZ implementation aligned to your identity requirements
Data integration layer and persistence approach
Automated test suite appropriate to the scope (unit + integration where needed)
Deployment approach and CI/CD pipeline recommendations (and implementation where in scope)
Operational readiness: logging, health checks, and runbook notes for support
Handover pack: documentation, environment notes, and next-step backlog

How It Works

Discovery to confirm domain requirements, consumers, data sources, and non-functional needs
API contract design including resources, validation rules, error models, and versioning approach
Implementation in FastAPI or Node.js with authentication and authorisation aligned to your identity model
Data and system integration including persistence, external APIs, and message or event patterns as needed
Testing and quality checks including unit and integration coverage appropriate to risk
Deployment preparation including CI/CD, environment configuration, and observability setup
Handover with documentation, runbooks, and a backlog for enhancements

Engagement Options

New API Build - Design and implementation of a new backend service with OpenAPI documentation
API Extension - Add endpoints, integrations, or features to an existing API
Stabilisation - Improve reliability, performance, security, and observability for a current API
Platform Alignment - Prepare the API for Azure App Service, Container Apps, or Kubernetes deployment

Common Bundles

Customers who use this service often bundle with these services

API & System Integrations
Design and implement API integrations connecting business systems with secure authentication, retries, logging, and supportable middleware patterns operations.

Microsoft Graph API Integrations
Build secure Microsoft Graph integrations for Microsoft 365 automation, using app registrations, least privilege permissions, auditability, and documented operational controls.

SSO & Enterprise App Integrations
SSO and enterprise application integrations using Microsoft Entra ID, standardising access, authentication, and user lifecycle management across SaaS platforms.

MCP Server Builds & Tool Integrations
Build secure MCP servers and tool integrations that expose data and actions to AI agents with governed access and deployment.

Database Design, Engineering & Optimisation
Design, optimise and stabilise application databases with clean schemas, efficient indexing, strong security controls, and predictable performance under real workloads.

Azure Landing Zones (CAF-aligned)
Build a secure, scalable Azure foundation using CAF-aligned landing zones with clear governance, identity, networking, and management baselines.

Frontend Engineering (React/TypeScript)
Deliver React and TypeScript frontends focused on performance, accessibility and maintainability through component systems, clean architecture and integration ready builds.

UI/UX Design for Applications
Application UI and UX design producing build ready prototypes, tested journeys, and accessible interfaces aligned to real user workflows.

Kubernetes & AKS Engineering
Engineer Kubernetes and AKS platforms with clear architecture, secure access, scaling, ingress and observability so teams can deploy and operate confidently.