API Development · Sydney, NSW
Connect your systems so data flows, not people.
Your payroll system does not talk to your rostering system. Your CRM does not talk to your compliance platform. Staff manually move data between systems, introducing errors and wasting hours. Human Nexus builds APIs and integrations that connect your systems into a single operating layer, so data flows automatically and your team does the work that matters.
REST + GraphQL
Modern API standards
300+
Automation processes deployed
Fixed
Price, every integration
Sydney
Australian team
The problems we fix.
Your systems do not talk to each other
Payroll, rostering, CRM, compliance, and finance systems each hold critical data but operate in isolation. Staff manually export, reformat, and re-enter data, introducing errors and delays every cycle.
Vendor APIs are poorly documented or nonexistent
Many operational systems have incomplete APIs, rate limits, or no API at all. We build integration layers that handle these constraints: polling, webhooks, file-based integration, and screen scraping where necessary.
Integration projects stall in discovery
Six months of architecture diagrams and vendor negotiations before any code runs. We build a working integration in the first sprint so you see real data flowing while the architecture evolves.
How we deliver it.
01
System audit
We map every system in your operations, catalogue available APIs and data formats, and identify the highest-value integration points. Delivered as a one-page integration map.
02
API design
OpenAPI specification for REST APIs or GraphQL schema definition. You review the contract before we write code. Clear data models, authentication patterns, and error handling.
03
Build and test
APIs built against the agreed specification. Integration tests against your live systems (or sandboxes). Load testing for production volumes. Error handling for every failure mode we can anticipate.
04
Deploy and monitor
APIs deployed to your cloud environment with monitoring, alerting, and logging. Documentation for your internal teams. 30 days of post-launch support.
What's included.
REST API development
OpenAPI 3.0 specification, Node.js or Python backends, JWT/OAuth2 authentication, rate limiting, versioning, and comprehensive error handling. Built for production from day one.
GraphQL API development
Single endpoint serving exactly the data each client needs. Schema-first design with Apollo or Relay. Ideal for mobile apps and complex data relationships.
System-to-system integration
Payroll to rostering, CRM to compliance, finance to operations. Bi-directional sync, conflict resolution, and audit trail. Built on your infrastructure, not a third-party iPaaS.
Custom connectors for legacy systems
Systems without modern APIs still hold critical data. We build connectors using file-based integration, database-level access, or screen scraping where no other option exists.
Webhook and event-driven architecture
Real-time data flows using webhooks, message queues (RabbitMQ, SQS), and event-driven patterns. Systems react to changes immediately, not on a nightly batch cycle.
API gateway and management
AWS API Gateway, Azure API Management, or Kong. Centralised authentication, rate limiting, monitoring, and developer portal for your internal and external API consumers.
Why Human Nexus.
Working integration in the first sprint
Not a six-month architecture project. We build a working integration that moves real data within the first development sprint. You see value while the full solution evolves.
Built on your infrastructure
APIs run on your AWS, Azure, or GCP account. No third-party iPaaS dependency. No per-transaction fees. Full control over data residency and security.
You own the API code
Full source code, OpenAPI specs, deployment scripts, and documentation handed over. Your internal team can extend, modify, and maintain the APIs independently.
Handles real-world system constraints
We design for vendor API rate limits, unreliable endpoints, inconsistent data formats, and systems that go offline. Graceful degradation, not cascading failures.
Australian data residency
APIs deployed in Sydney (ap-southeast-2) or Australian Azure regions by default. Data never leaves Australian jurisdiction unless you explicitly require it.
Fixed price, clear scope
Each integration scoped and priced before development starts. No open-ended billing. Additional systems or endpoints priced separately with your approval.
Proof of work
300+ automation processes integrated across critical back-office systems.
Human Nexus designed and deployed over 300 automated processes for a large Australian care provider, connecting payroll, rostering, HR, and compliance systems that previously required manual data transfer between platforms.
$430K per fortnight saved through system integration.
Common questions.
How much does API development cost?
Simple two-system REST API integrations start from $10,000 to $20,000. Complex multi-system integrations with event-driven architecture range from $30,000 to $80,000. Enterprise integration platforms range from $80,000 to $200,000. Fixed-price quotes after a free system audit.
How long does it take to build an API integration?
Working data flow in the first week. Simple point-to-point integrations: two to four weeks. Multi-system orchestration: four to eight weeks. Enterprise integration platforms: eight to sixteen weeks with phased delivery.
What if our systems do not have APIs?
We build integration layers for systems without modern APIs. Options include database-level access (read-only where possible), file-based integration (SFTP, CSV, XML), and structured screen scraping as a last resort. We advise on the right approach during the system audit.
How do you handle data security and privacy?
All APIs use TLS 1.3 encryption in transit. Data at rest is encrypted using AES-256. Authentication via JWT, OAuth2, or API keys. Australian Privacy Principles compliance by design. Data residency in Australian cloud regions by default.
Can you work with our existing iPaaS or integration platform?
Yes. We build on your existing investment in platforms like Workato, Boomi, MuleSoft, or Azure Logic Apps. We also build custom APIs that complement rather than replace your existing integration layer.
What happens after the APIs are deployed?
30 days of post-launch support including monitoring, alerting, and incident response. We provide API documentation for your internal teams. Ongoing maintenance packages available for monitoring, vendor API changes, and enhancement requests.
Which two systems would you connect first?
Book a free 30-minute system audit. We will map your integration landscape and identify the highest-value connection point.
Book a free assessment
Tell us about your process. We'll reply within one business day.