Senior C# / .NET Developer (Windows Services + REST API Integration) for Healthcare Booking Platform

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: TYPE OF WORK

Gig

: SALARY

1800-2200pm

: HOURS PER WEEK

40

: DATE UPDATED

Aug 21, 2026

JOB OVERVIEW

TYPE OF EMPLOYMENT
Full Time

JOB DESCRIPTION

IMPORTANT: Start your application with the word BOOKED and answer the three questions at the bottom. Applications that skip either will not be read.

We are an Australian company building an online appointment booking product for healthcare practices. Patients book on a branded web page, the appointment writes directly into the practice's existing practice management software in real time, and a confirmation event (never patient data) is sent to our analytics service. Part of the web layer already exists in production. You will build the integration layer.

What you will build:

A Windows service agent (C# / .NET) that installs on a practice PC, holds an outbound-only connection to our cloud (no inbound ports), auto-updates, and reports health
An adapter to the practice software's local REST/OData API: read availability, create, update and cancel appointments (full API documentation provided after NDA)
Patient matching logic that finds the correct existing record with a confidence threshold and a safe fallback, and never creates duplicates
Idempotency and concurrency handling: a retried request must never create two appointments, and two patients must never take the same slot
A webhook posting confirmed-booking events to our analytics service
Fleet tooling: auto-update pipeline, health monitoring, alerts

Requirements:

Strong C# / .NET including Windows services, not only web APIs
You have shipped software that runs unattended on customers' machines: installers, self-update, and diagnosing faults you cannot reproduce locally
REST and OData integration against third-party APIs you do not control
Queuing, retry and idempotency patterns
Careful work against live production databases you must not corrupt
Good written English and at least 4 hours daily overlap with Sydney time
Nice to have: healthcare, dental or veterinary software integration; Azure

How we will hire:

NDA first, then a small paid trial task, then full-time engagement
Long-term role for the right person
All work is IP-assigned to our company
We work in a code-named brief; real system names are shared after NDA only

Answer these three in your application:

Describe something you built that runs on a customer's machine. How did it update itself, and how did you diagnose a fault you could not reproduce?
A booking API call times out and you do not know whether the appointment was created. What exactly does your design do next?
A returning patient types their name slightly differently from the database record. How does your matching d ---------- , and what happens when it is not confident?

SKILL REQUIREMENT

C# .Net REST API

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Senior C# / .NET Developer (Windows Services + REST API Integration) for Healthcare Booking Platform

Please login or register as jobseeker to apply for this job.

TYPE OF WORK

SALARY

HOURS PER WEEK

DATE UPDATED

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