FastAPI Development Services for Australian SaaS, AI, and Data Teams
FastAPI development is the building of high-performance, async Python APIs and microservices with the FastAPI framework, the service layer modern SaaS, data, and AI products run on. MicroPyramid has 12+ years of Python and API work and ships these for Australian startups and SMBs: async APIs, microservices, and ML/LLM serving layers built for real concurrency.
Why Australian Teams Choose Us for FastAPI
Three reasons Australian founders and product teams pick MicroPyramid over a local agency or a generic offshore team
Privacy-Aware API Design
Personal data flows across APIs, third-party services, and automated decisions, so we design the API surface, logging, retention, and overseas service calls with privacy in mind from the first sprint. AWS ap-southeast-2 (Sydney) available for Australian data residency.
AUD Billing via Stripe
Invoices in Australian dollars, collected via Stripe. No currency conversion surprises, no international wire fees. Clean billing that fits how Australian businesses actually operate.
Clear Ownership, Not a Ticket Mill
Experienced engineers directly own every engagement. You will not be passed to a delivery layer of junior developers. The engineer who scopes your API in discovery is the one who builds it.
Australian APIs and Integrations We Build With FastAPI
Australian products plug into a familiar mix of services: ATO reporting channels, Peppol e-invoicing, FHIR health data, Xero and MYOB, Stripe billing, and the queues and workers that keep slow calls off the request path. These are the integrations we build most often for Australian teams, and what doing them properly involves.
Event Queues and Background Jobs
SQS, Redis, Kafka, or Celery and arq workers
Slow third-party calls such as ATO submissions, accounting sync, or LLM batches should never hold an API request open. We move that work onto queues and workers so your FastAPI endpoints answer in milliseconds, and every job can be retried, inspected, and recovered when an upstream misbehaves.
- Queue and worker setup on SQS, Redis, Kafka, or Celery
- Retries with exponential backoff and dead-letter queues
- Idempotent consumers that are safe to replay
- Job status endpoints your frontend and support team can poll
Stripe and Payment Webhooks
Subscriptions and one-off payments in AUD
Most Australian SaaS products take subscriptions and one-off payments through Stripe or a similar provider. The hard part is keeping your own records in step with theirs. We build the FastAPI side: verified webhooks, idempotent handlers, subscription state your app can trust, and a daily job that catches anything missed.
- Webhook signature verification and idempotency keys
- Subscription lifecycle: trials, upgrades, pauses, cancellations
- Refunds and failed-payment handling
- Daily reconciliation job against provider records
ATO Reporting and Single Touch Payroll
Standard Business Reporting channels, STP Phase 2
Payroll, accounting, and practice software reports to the ATO through Standard Business Reporting channels, including Single Touch Payroll Phase 2. Many products send through a sending service provider rather than building SBR messaging directly; we help you pick the route and build it.
- STP Phase 2 pay event payloads and validation
- Sending service provider integration
- Authentication, encryption, and audit logging controls
- Submission status tracking and resubmission
Peppol e-Invoicing
Australia’s e-invoicing network, via accredited access points
Australia uses the Peppol network for e-invoicing, and businesses connect through an accredited access point. We build FastAPI services that generate and validate Peppol A-NZ invoice documents, send and receive them through your access point provider, and match inbound invoices to purchase orders.
- Invoice generation and schema validation
- Access point provider integration
- Inbound invoice matching to purchase orders
- Delivery and response status tracking
Health Interoperability (FHIR AU)
HL7 Australia AU Base and AU Core profiles
Australian health software increasingly exchanges data as FHIR using HL7 Australia’s AU Base and AU Core profiles, while many practices still send HL7 v2 messages. National services such as My Health Record require conformance-tested integrations. We build FHIR-native FastAPI services, map legacy messages, and keep the access audit trail health providers expect.
- FHIR R4 validation against AU Core profiles
- HL7 v2 to FHIR mapping
- Consent-aware access control
- Access audit logging per record
Xero, MYOB, and Business Data
The accounting platforms Australian SMBs already run on
Australian SMB software rarely lives alone. We build FastAPI sync services against Xero and MYOB APIs, plus ABN Lookup for business verification, with OAuth token rotation, rate-limit-aware queues, and conflict handling so invoices, contacts, and payments stay consistent.
- OAuth token storage and rotation
- ABN Lookup verification at onboarding
- Rate-limit-aware background sync
- Per-tenant sync status your support team can see
Our FastAPI Development Services
Six services covering the full lifecycle of high-performance Python APIs, from async builds and microservices to ML serving and migration
High-Performance Async APIs
Async FastAPI services for Australian SaaS, energy, and AI products that fan out to many slow upstreams at once: LLM providers, energy retailers, accounting platforms, and ATO channels. Async I/O keeps one sluggish provider from stalling every other request.
- Async/await concurrency
- Pydantic v2 validation
- Automatic OpenAPI docs
Microservices Architecture
Split an Australian platform into services with clear boundaries: customer accounts, billing and webhooks, reporting, notifications, background jobs. Isolating sensitive personal data in its own service makes privacy controls far easier to evidence.
- Sensitive-data isolation
- Docker and Kubernetes
- REST plus event queues
AI & ML / LLM Serving APIs
Streaming LLM endpoints, RAG services, and model-serving APIs with the records a privacy review asks for: which overseas provider sees personal data, and logged inputs for automated decisions.
- Model and LLM serving
- Server-sent event streaming
- Decision and disclosure logging
Migration to FastAPI
Move legacy Flask, Django REST, or synchronous APIs onto async FastAPI endpoint by endpoint, behind the same URLs your Australian customers, integrators, and partners already call. Contract tests prove each cut-over before traffic moves.
- Phased, low-downtime migration
- Contract tests against the old API
- Performance audit first
Maintenance & Support Retainers
Security patching, dependency upgrades, provider API version changes and deprecations, and feature work for FastAPI services in production, with end-of-day handoffs timed for your Australian team to review first thing.
- Security and dependency updates
- Provider API version upgrades
- Feature work alongside your team
Cloud Deployment & DevOps
Deploy FastAPI to AWS ap-southeast-2 (Sydney) when Australian data residency matters, with ap-southeast-4 (Melbourne) available as a second region. CI/CD, structured logs, tracing, and infrastructure as code your auditors can read.
- AWS ap-southeast-2 (Sydney) deployment
- CI/CD with GitHub Actions
- Infrastructure as code
FastAPI, Django REST, or Flask? How to Choose
The three frameworks solve different problems, and real Australian products often mix them. Here's the honest version, so you pick the right tool instead of the trendy one. We help you make the call in discovery, before any budget is committed.
Choose FastAPI when…
- You need a high-performance, type-safe API or microservice
- You're serving AI/LLM features, RAG endpoints, or heavy async I/O
- OpenAPI-first contracts and Pydantic validation are priorities
- You want a lightweight service, not a full web framework
Choose Django REST when…
- You want a full web app (admin, auth, and ORM) plus its API
- You're building a SaaS, portal, or content-driven product
- Convention-over-configuration and a large ecosystem matter most
- Raw async throughput is not the dominant constraint
Choose Flask when…
- You have a small, simple service with minimal dependencies
- You want maximum freedom over structure and libraries
- Async and built-in validation are not requirements
- You are maintaining an existing Flask codebase, not starting fresh
Need a full Django web app rather than a standalone API? See Django Development for Australian Teams, or broader Python work: Python Development Services.
Best Fit For
- Australian SaaS, energy, and AI teams that need high-throughput, auditable Python APIs
- products integrating Stripe billing, ATO reporting, Peppol e-invoicing, or Xero and MYOB sync
- teams serving ML models or LLM features that need streaming and privacy-aware logging
- migrations from slow Flask or Django REST APIs to modern async FastAPI
Not the Right Fit When
- simple CRUD admin tools where a full async API offers no real benefit
- engagements looking only for staff augmentation without delivery ownership
- pure frontend or marketing-site work with no API or backend complexity
- teams wanting an API rewrite with no measurable performance or scaling problem to solve
Need broader Python work beyond APIs? See Python Development Services, or serving AI features inside your product, see AI Feature Development.
Our FastAPI & Python Stack
Modern async technologies and proven patterns, deployed to AWS ap-southeast-2 (Sydney) for Australian data residency
Core Framework
Data & Storage
DevOps & Cloud
How to Get Started as an Australian Team
We recommend starting with an API Discovery Sprint: clarify the workload and architecture before committing to a full build. All engagements billed in AUD via Stripe.
API Discovery Sprint
Recommended start
Clarify the workload, data contracts, throughput targets, and architecture before committing to a full build. Billed in AUD, delivered with daily async updates and a fixed estimate at the end.
- Workload and throughput analysis
- API and schema design
- Architecture and scaling plan
- Migration assessment if relevant
API Build Sprint
Ship a production-ready FastAPI service or set of microservices with async foundations that are genuinely ready to scale, not a throwaway prototype.
- Production-ready async API
- Pydantic models and OpenAPI docs
- Clear deliverables and timeline
Maintenance & Retainer
Ongoing FastAPI maintenance, performance tuning, and feature work end-to-end, with end-of-day handoffs timed for your Australian team to review first thing.
- Security and dependency upkeep
- Performance and scaling work
- Retainer or time-and-material
Selected Work
FastAPI services and API products we have built and shipped, each linked to its case study.
DiscoveredBy
AI search visibility platform that tracks how brands appear in ChatGPT, Gemini, Perplexity, Claude, and Grok, built with FastAPI, SvelteKit, and AI agents.
Read case studyOnlineCompiler.io
Sandboxed code execution platform for 12 languages with a REST API, WebSocket support, an embeddable widget, and MCP support for AI agents.
Read case studyIntentport
Our voice and text AI agent for websites: answers from live business data, books appointments, and sends qualified leads to the CRM in five languages.
Read case study
CREDITABLE
Employee financial wellness platform covering savings, workplace loans, and repayment workflows, built on Django and FastAPI.
Read case studyFastAPI Development FAQs for Australian Teams
Straight answers to what Australian founders and CTOs ask us before starting a FastAPI project.
What drives the cost of a FastAPI project?
The main drivers are scope and endpoint count, the complexity of your data model, how many providers you integrate (LLM providers, Stripe, ATO channels, Peppol access points, Xero or MYOB), whether you need real-time or streaming features, and the compliance evidence your sector expects. A single microservice is a very different job from a multi-service platform holding health or payroll data. We give a fixed estimate in AUD after a short discovery sprint rather than running an open-ended hourly meter.
Can FastAPI handle slow third-party integrations without slowing the API?
Yes. We keep request handlers fast and push slow work, such as ATO submissions, Xero or MYOB sync, Stripe webhook processing, and LLM batches, onto background queues with retries and dead-letter handling. Each integration sits in its own service or worker with its own access path, so one provider can change or fail without reworking the rest.
Can you integrate with the ATO for payroll or tax reporting?
Yes. We build Single Touch Payroll Phase 2 and other Standard Business Reporting integrations, either directly or through a sending service provider, with strong authentication, encryption, audit logging, and appropriate data hosting designed in. We also build Peppol e-invoicing through your chosen access point and sync with Xero and MYOB.
How do you handle personal data in AI and automated-decision APIs?
We record which decisions are automated and what data they use, and we take care when personal data goes to overseas recipients, which includes most LLM providers. We log decision inputs, keep a register of external model calls, and can route sensitive workloads to models hosted in Australia.
Is FastAPI fast enough compared to Node.js or Go?
For most API workloads, yes. FastAPI runs on async Starlette and Uvicorn and delivers throughput in the same class as Node.js and close to Go for typical I/O-bound APIs, while keeping Python’s ecosystem for data and AI. Go still wins for extreme CPU-bound or ultra-low-latency cases, but for AI service layers, data-heavy APIs, and most SaaS and data backends, FastAPI is fast enough and far quicker to build.
Why is FastAPI the standard for AI and LLM backends?
FastAPI is async by design, so it handles the long-lived, concurrent connections that LLM calls and streaming responses require, and it sits in Python, the native language of AI tooling like LangChain, vector databases, and model SDKs. That makes it the natural place to build RAG endpoints, model-serving APIs, streaming chat, and agent backends without a separate stack.
Can you migrate our Flask or Django REST API to FastAPI?
Yes. We audit the existing API, identify async and performance bottlenecks, and migrate to FastAPI incrementally, running services side by side and cutting over endpoints without downtime, rather than risking a big-bang rewrite that destabilises the product your Australian customers rely on. Many engagements start as a migration and performance audit sprint.
Where will our API and data be hosted?
For Australian products we usually deploy to AWS ap-southeast-2 (Sydney), multi-AZ, with ap-southeast-4 (Melbourne) available when you want a second Australian region for disaster recovery. Personal data, backups, and logs stay onshore, and we document every overseas service an endpoint calls. Privacy is considered from the first architecture session, not bolted on before launch.
How does billing work for Australian teams?
We invoice in Australian dollars and collect via Stripe, and structure engagements around fixed-scope sprints or a monthly retainer.
Do we own the source code and IP?
Yes. You own all source code and intellectual property we produce for you. Everything is committed to your repositories as we build, so there is no lock-in and no handover risk if you later bring the work in-house or move to another team.
Ready to Build a Fast, Reliable API?
If you need a team to build or scale FastAPI services (with AUD billing and privacy designed in), we are ready to talk. No junior handoffs, no ticket mills. Just high-performance API engineering for Australian teams.