Services

Custom Software Development in Sydney

Sentia is a custom software development company in Sydney, building for Australian businesses since 2006. We design web platforms, integrations and apps around how your team actually works, and the web applications we've built serve more than 15 million users.

Tell us about your project

Fits how you work. Lasts as you grow.

Built around your workflow.

Off-the-shelf tools make you work their way. We start from how your team actually operates, build to match, and integrate with the systems you already use.

Built to last.

Systems we built at startup stage are still running at scale today. Tested, maintainable code is how your software keeps up as the business changes.

You always know where your budget is going.

Custom builds drift when scope isn't managed. We scope carefully, tell you when things change, and don't build what you don't need. Honest updates on progress and cost throughout.

What we build

Custom software development services for Australian businesses.

Web applications

Web applications

Platforms, marketplaces, SaaS products and operational tools, scoped so that version one ships.

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Marketplaces

Payments, search and trust flows that work for both sides.

SaaS products

Subscription billing, multi-tenant setups and role-based access built in.

Operational tools

Replace spreadsheets and manual follow-up with software that runs the work.

Version one first

Scoped so the first release ships, then grows with you.

Ruby on Rails

Ruby on Rails

Two decades of building and maintaining Rails applications in Australia.

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New Rails builds

Rails, PostgreSQL and Hotwire, set up to grow without rewrites.

Existing applications

Take over, maintain and extend Rails apps other teams started.

Background jobs

Sidekiq queues for the work that shouldn't make users wait.

Test-driven code

Tests written as we build, so changes don't break what works.

APIs and integrations

APIs and integrations

Connect your systems, payment providers and third-party platforms so data moves without manual re-entry.

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Payments

Stripe, Airwallex, Zai and PayTo, from checkout to reconciliation.

Accounting and ERP

Connect invoicing and accounting platforms such as Xero.

Your own API

REST APIs your apps, partners and customers can build on.

Events and webhooks

Data that moves as things happen, not on a schedule.

Enterprise software

Enterprise software

Systems for larger organisations, with more users, more integrations and more to get right.

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Roles and permissions

Control who sees, edits and approves what across teams.

Audit trails

Records of who changed what, ready for compliance reviews.

Phased replacement

Replace ageing systems in stages, without stopping operations.

Connected systems

Linked to the ERP, finance and reporting tools you already run.

Custom software developers who ship early and test as they go.

Working software early.

Working software early, so feedback arrives while changes are still cheap. We build in short cycles and show you what exists, not what's planned.

Test-driven and agile.

We specialise in test-driven development, extreme programming and agile methods, so what we ship keeps working as the system grows.

You stay close to the build.

We work closely with you throughout, from first scoping conversation to launch and beyond.

Our work

Airtasker

Airtasker

Marketplace connecting people to complete everyday tasks and services

Branche

On-demand Service, Marketplace

Shippit

Shippit

Delivery platform that makes shipping easy and efficient for businesses

Branche

Transport & Logistics, Retail & eCommerce

Eclipx Car Inspections

Eclipx Car Inspections

Streamlining full lease return journey — from booking to inspection to final vehicle handover

Branche

Transport & Logistics

Boardroom

Boardroom

Shared registry access for investors and employees

Branche

Financial Services & Fintech

RANGEme

RANGEme

A Network of Savvy Buyers and Suppliers

Branche

Marketplace, Retail & eCommerce

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Common questions

Every project is different. Send us your brief and we'll give you a detailed estimate, free of charge.

It depends on scope. Before we quote, we work through what the first version needs, so the timeline reflects the work and not a guess. You'll see working software early, while feedback is still easy to act on.

There are two options. You can move into support and maintenance, which we can manage, or keep developing while we support the current version. Support is tailored to what you need.

Yes. We can provide a mutual NDA that protects your IP and ours.

Yes. We work with clients at every stage, from early ideas to fully specified concepts. If you know what you need, we'll still draw on our experience to help you get the most from it.

We specialise in Ruby on Rails for web applications, and build iOS, Android and React Native mobile apps.

Sentia is based in Sydney. We build software for Australian businesses of all sizes, with our Zagreb team adding delivery capacity.