Senior Full Stack Developer – SaaS & AI - with vibe coding experience

Senior Full Stack / SaaS Developer - with vibe coding experience

Sydney | Contract / Full-Time | 3–12 Months

We are looking for an experienced Senior Full Stack / SaaS Developer to help further develop, scale and secure an advanced proprietary business platform.

Candidates should be experienced in building, improving and developing internal, client-facing and supplier-facing workflow management, procurement, reporting, logistics and business automation software and be experienced with working with vibe coding tools as well as traditional coding.

What You’ll Do

• Build and develop new systems as required by the business teams

• Review and improve the existing application architecture

• Strengthen security, authentication, MFA and permissions

• Review multi-tenant data separation and Row Level Security

• Secure database, file storage, APIs and backend functions

• Build and maintain third-party integrations

• Improve performance, scalability and maintainability

• Refactor and develop frontend/backend functionality

• Introduce automated and security testing

• Provide ongoing technical guidance

Skills We’re Looking For

Strong experience with:

• React / TypeScript / JavaScript

• Node.js

• PostgreSQL / SQL

• Supabase or similar backend platforms

• REST APIs / Webhooks

• Multi-tenant SaaS architecture

• Authentication and role-based permissions

• Application security

• Git / GitHub

AI-Assisted Development Experience

Experience with modern AI-assisted development tools such as Lovable, Cursor, Replit, Bolt or similar platforms is highly desirable.

However, we are not looking for someone whose experience is limited to prompting AI tools.

You should be comfortable:

• Reviewing AI-generated code

• Working directly in an existing codebase

• Debugging independently

• Writing custom application logic

• Writing SQL

• Creating secure database policies

• Building backend functions

• Integrating external APIs

• Refactoring code where required

• Reviewing application security independently

We are looking for someone who can combine the speed of modern AI-assisted development with proper software engineering discipline.

Engagement

Initial engagement is expected to be approximately 3–6 months, with the potential for an ongoing relationship.

Sydney-based candidates are preferred, as we would require you to work initially from our offices in Pyrmont to understand the needs and requirements of the business, followed by a hyrid working model thereafter. Strong remote candidates within Australia may also be considered.

About You

You are a senior, hands-on developer who can work independently, understand business workflows quickly and combine modern AI-assisted development with strong software engineering discipline.

We are ideally looking for an experienced individual developer or consultant rather than a large agency.

To Apply

Please provide:

• Relevant full-stack / SaaS experience

• Examples of applications you have developed

• Security and multi-tenant experience

• AI-assisted development experience

• Availability

You can find out more about our business at www.sem.com.au