Senior Backend Engineer - Relocate to San Francisco (Aus Founder + relo support)

This role is based in San Francisco, not Australia - we are trying something a little different to attract talent.

Airtree has recently invested in an Aussie-founded startup building the next generation of B2B software infrastructure. Your application will be reviewed by our portfolio company and they will contact you for an interview if successful.

This is your opportunity to join an Australian-founded startup with a team in SF, at the ground floor — with a relocation package to SF and visa sponsorship for Australians ready to make the move to the US.

Below is a description of the role from the company.

You'll be joining the founding engineering team in San Francisco, working alongside the Australian founder and a small, world-class team of engineers. You'll have the chance to shape the technical foundation of a platform that's redefining how software is bought and sold, while experiencing life in one of the world's most dynamic tech ecosystems.

We'll handle the logistics: relocation support, visa sponsorship, and help getting set up in the US — so you can focus on doing your best work.

What you'll do

• Design and build the core backend services that enable complex, asynchronous workflows across multiple systems
• Create the foundational frameworks used across the engineering team to power new product capabilities
• Own key design and architectural decisions, from scalability to resilience to developer experience
• Work closely with product and leadership to define how we build for speed, scale, and quality
• Set engineering standards, mentor peers, and help shape a high-performance culture

Who you are

• A systems thinker who designs for resilience, scalability, and observability
• Pragmatic and product-minded, balancing technical excellence with startup agility
• Passionate about developer experience, and building tools that empower others
• Excited by the chance to own greenfield systems from day one and influence long-term architecture
• Strong communicator who thrives in a fast-moving, collaborative environment.

Your background

• 5+ years of backend engineering experience, building and operating distributed systems
• Strong expertise in a modern backend language — Python, Go, Java, or similar
• Deep understanding of event-driven design, message queues, and asynchronous systems
• Experience with AWS/GCP and containerised environments
• Solid grasp of API design, data modelling, and database architecture
• (Bonus) Experience with orchestration engines, developer tools, or SDKs.

Ready to make the move?

Join a team that's moving fast, thinking globally, and building something with massive scale.

If you're an Australian engineer ready to take your career to Silicon Valley — this is your moment.

What we offer

• Relocation + visa sponsorship for Australians
• Competitive salary and meaningful equity — build what you own
• Unlimited paid time off, with a minimum recharge expectation
• Dedicated career development and learning allowances
• Fitness and mental health benefits
• A chance to live and work in San Francisco, while staying connected to the Australian startup community.