Principal Backend Python Engineer

A green-field opportunity to shape the architecture, systems and engineering standards of an ambitious AI product.

About Maddyie Labs

Maddyie Labs is building LiMSight, an AI-native platform for regulated laboratory and scientific environments. We are focused on environments where proof matters: laboratories, scientific teams, quality systems, regulated workflows, and organisations where evidence, traceability, provenance, auditability and human judgement are critical. Our belief is simple: AI should not obscure accountability. It should make accountability easier to see. LiMSight brings together AI, knowledge graphs, retrieval-augmented generation, workflow automation, data provenance, evidence orchestration and human-in-the-loop validation to help regulated teams work faster without losing trust, context or control.

About the role

We are looking for a Senior / Principal Backend Python Engineer to help design and build the core backend systems behind LiMSight. This is not a ticket‑taking role. You will help shape the backend architecture, technical standards, integration patterns and engineering foundations that future product and engineering teams will build on. The platform will support AI‑assisted workflows, secure enterprise access, document and data processing, Graph Retrieval‑Augmented Generation, embeddings, vector search, and integrations with customer systems. It needs to work in environments where reliability, security, auditability and evidence matter. You will suit this role if you enjoy building robust backend systems, making thoughtful technical decisions, working with ambiguity, and creating foundations that can scale.

Why this role matters now

Maddyie Labs is at the stage where early technical decisions will have long‑term consequences. The person in this role will help establish:

• the backend architecture
• the Python service foundations
• authentication, authorisation and RBAC patterns
• data and AI integration approaches
• testing and quality standards
• deployment and runtime patterns
• engineering practices for future hires

This role is important because the company is not just building features. It is building the technical foundation for a platform that needs to be secure, maintainable, scalable and trusted.

What you will do

• Design and build backend services in Python to support LiMSight’s core product capabilities.
• Help establish the backend architecture and technical patterns for the platform.
• Build reliable, scalable and extensible services that can support both customer‑managed and cloud‑managed deployment models.
• Develop and integrate Role‑Based Access Control frameworks, working with customer authentication and authorisation systems.
• Implement services that support embeddings, Graph RAG, document processing, vector search and AI‑assisted workflows.
• Work with the team to make thoughtful framework, tooling and architecture decisions.
• Build with maintainability, testability, security and extensibility in mind.
• Validate your work through unit, integration and system testing.
• Collaborate closely with product, technical leadership and future engineering hires.
• Help create engineering standards that allow the team to grow without accumulating unnecessary technical debt.

What we are looking for

Required experience

• Strong professional experience in software engineering or an equivalent backend engineering role.
• Strong Python capability and familiarity with Python’s ecosystem.
• Good understanding of software design principles, clean code, SOLID principles, testing and maintainability.
• Experience building or contributing to production systems.
• Ability to reason clearly about technical tradeoffs.
• Ability to work independently in an early‑stage environment.
• Clear communication and willingness to collaborate closely with a small team.
• Full working rights in Australia.

Highly valued experience

• FastAPI, asyncio, Pydantic or similar modern Python backend frameworks.
• Authentication and authorisation frameworks such as LDAP, OIDC or SAML.
• RBAC or enterprise access control models.
• AI/ML‑enabled backend systems.
• Embeddings, vector databases or vector search systems such as Chroma, Pinecone, Weaviate or Milvus.
• RAG architectures, including document preprocessing, chunking, retrieval and hybrid search.
• Graph RAG, knowledge graphs or graph‑backed data systems.
• LLM API integrations such as OpenAI, Anthropic or similar.
• Prompt orchestration frameworks or AI application infrastructure.Docker, GitHub Actions, CI/CD and developer tooling.
• Systems that require auditability, traceability, security or regulated customer environments.
• Early‑stage, startup, scale‑up or product‑building environments.

The type of person who will thrive here

• like building from first principles
• want meaningful ownership rather than narrow task execution
• can operate without every process already being defined
• care about quality, reliability and maintainability
• can move between hands‑on delivery and architectural thinking
• enjoy learning new domains quickly
• communicate clearly and directly
• want to help shape the company, not just occupy a role within it

This role will not suit someone who needs a fully mature structure, a large engineering team around them, or a tightly defined corporate ladder from day one.

Why join Maddyie Labs

• Ground‑floor impact: Help shape the product, architecture and engineering culture early.
• Serious technical challenge: Build AI‑native systems for environments where trust, evidence and accountability matter.
• High ownership: Make meaningful decisions that influence the company’s technical direction.
• Real‑world AI: Work on practical AI infrastructure, not hype‑driven prototypes.
• Growth opportunity: As the company grows, early hires will have the opportunity to grow with it.
• Inclusive culture: Join a team that values authenticity, learning, accountability and respect.
• Flexible work: Work in a way that supports both delivery and life outside work.

Location

Melbourne is preferred, particularly while the company is building its early team and operating rhythm. Strong candidates in compatible Australian time zones may also be considered.

How to apply

If this role sounds like you, please apply with your resume and any links that help us understand your work, such as GitHub, technical writing, open‑source contributions, portfolio projects or relevant product examples. We know strong candidates do not all follow the same path. If your experience is close but not a perfect match, and you believe you can do excellent work in this role, we encourage you to apply.

Maddyie Labs is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all team members.