AI Receptionist System / Twilio / OpenAI / Retell AI / Supabase

Company Overview

We are an Australian real estate sales and project marketing business looking for a reliable part-time developer to maintain and improve an existing AI receptionist system.

This is a remote freelance / part-time role suitable for a developer with strong backend, API integration, automation, and AI voice system experience.

Project Overview

The current system is an AI receptionist that handles inbound phone enquiries, speaks with callers, captures caller details, matches enquiries to property projects, and sends lead notifications to the correct salesperson.

The first priority is to maintain and stabilise the current V1 system, fix bugs, document the setup properly, and ensure the system runs reliably. Once V1 is stable, we will move into V2 upgrades as a separate paid project.

Current Tech Stack

The system currently uses:

- OpenAI API

- Retell AI

- Twilio

- Supabase

- Render

- GitHub

- SMS / email notifications

- Google Sheets or lead allocation logic

- Webhooks and API integrations

- Real estate project matching workflow

Key Responsibilities

The developer will be responsible for:

- Reviewing the current system architecture

- Understanding how the current AI receptionist works

- Fixing bugs in the V1 system

- Maintaining Twilio / Retell AI / OpenAI / Supabase / Render integrations

- Debugging failed calls, failed SMS, email issues, or webhook problems

- Updating project matching and lead routing logic

- Making small prompt, wording, or workflow changes

- Keeping documentation up to date

- Providing clear written updates

- Advising on future improvements for V2

Phase 1 — Paid System Audit

The first task will be a paid system audit.

The audit should include:

- How the system currently works





- Key risks or weak points

- Required credentials and access

- Current bugs or likely failure points

- Deployment process

- Supabase / database structure

- Twilio / Retell AI / Render setup

- Recommendations to stabilise V1

Audit fee: AUD $250 fixed fee.

Phase 2 — Monthly Maintenance

After the audit, we are looking for ongoing monthly support.

Monthly retainer: AUD $600/month
Expected time allocation: approximately 10–12 hours per month

Included in monthly maintenance:

- Minor bug fixes

- System checks

- Small updates

- Prompt or logic adjustments

- Basic support

- Documentation updates

- Checking call flow issues

- Checking SMS / email notification issues

- Basic Supabase / Render / Twilio / Retell troubleshooting

- Response to system issues within agreed timeframe

The monthly retainer does not include major recent features, large rebuilds, or V2 development.

Any work beyond the agreed monthly maintenance scope will be quoted separately before proceeding.

Phase 3 — V2 Development

Once V1 is stable, we will move to V2 development as a separate paid project.

Possible V2 features include:

- Returning caller recognition

- Better call history

- Improved agent matching

- Improved project recommendation logic

- Duplicate enquiry handling

- Better SMS / email workflow

- Admin dashboard

- Reporting and analytics

- CRM-style lead tracking





- Integration with other business tools

V2 will be quoted separately with explicit milestones and payment stages.

Required Skills

The ideal candidate should have experience with:

- Backend development

- OpenAI API

- Twilio

- Retell AI or similar voice AI platforms

- Minimum of 6+ months hands-on experience with Retell AI or similar voice AI platforms is required

- Supabase

- Render

- GitHub

- Webhooks

- API integrations

- SMS / email automation

- Database design

- Debugging live production systems

Experience with CRM systems, voice automation, call automation, or lead routing is a bonus.

Candidate Requirements

We are looking for someone who is:

- Reliable and responsive

- Able to communicate clearly in English

- Able to document their work properly

- Comfortable maintaining an existing system

- Able to explain technical issues in simple terms

- Honest about what they can and cannot do

- Available for ongoing part-time support

- Interested in longer-term project work

Work Arrangement

- Remote role

- Freelance / part-time

- Paid in AUD

- Flexible hours, but must be responsive when system issues occur

- Long-term prospect if the working relationship is good

- Candidates from any location are welcome to apply

How to Apply

Please include:

1. Your experience with Twilio, Retell AI, OpenAI, Supabase, Render, or similar systems

2. Examples of similar systems you have built or maintained

3. Your hourly rate

4. Your availability

5. Your usual response time for urgent bugs

6. Whether you are willing to start with a paid technical audit

7. Any questions you have about the current system

Reliability, documentation, and communication are very important for this role.

📌 Remote Part-Time Backend / AI Voice Developer (Sydney)
🏢 Plus Notable
📍 Sydney