Senior Backend Engineer

About Block Earner

We are an innovative team with a bias to ship. Credit delivered through a digital asset platform and a tokenised credit engine is new territory in Australia, and most of what we build is being designed for the first time. We take on the harder version of a product, including being one of very few digital asset platforms here to do it as a licensed credit provider, put it in front of real customers, and keep moving. Where there is no precedent, we make one.

Backed by digital asset and DeFi veteran founders, and small enough that everyone's work is visible.

Our Track Record

• 🏦 Australian Credit Licence holder, lending under the consumer credit regime
• 🔐 ISO/IEC 27001 certified and SOC 2 Type 1 attested
• 🏆 Named a winner nine times by Australia's leading fintech bodies since 2024, most recently for Excellence in Consumer Lending
• 🤝 Our digital asset platform and tokenised credit engine power lending products for other Australian financial businesses
• 🌏 Live in Australia, expanding internationally

Location

This role is based in Sydney, working three days a week in the office and two from home.

The Role

We are growing the engineering team and looking for a Senior Backend Engineer to help build and harden the platform our lending products run on. The role suits someone with around 5 to 8 years of professional Java experience who wants real ownership over systems that move money.

You will design, build and run backend services in Java on AWS, working closely with product and the rest of engineering from the start of a piece of work rather than at the end of it. You will be trusted with whole services, not tickets, and expected to have opinions about how they should be built, deployed and secured.

Security is not a separate phase here. We hold customer funds, customer data and a credit licence, and the platform is used by partner businesses who build their own products on top of it. That means every design decision carries a security and reliability question with it: who can call this, what happens if it is retried, what does the audit trail look like, and how do we know when something has gone wrong. We want an engineer who asks those questions by instinct and enjoys answering them well.

The problems have real depth to them. Loan and collateral logic that has to be exactly right, technology that spans blockchain infrastructure and traditional financial rails, and regulatory obligations that shape what is possible to build. These are problems that reward digging in. The people who do well here get curious about how something actually functions, keep pulling at it until they understand it, and then find a smarter way through.

You do not need a background in digital asset platforms or a tokenised credit engine to start. You do need to be genuinely open to them, because you will be working with them every day.

Focus Areas

• Work AI-first. Write clear specifications and use the latest AI models and coding agents to turn them into production-quality code, then review, test and harden what they produce with the same rigour you would apply to your own.
• Help shape how the team builds with AI: the specs, conventions, guardrails and review practices that let us move faster without compromising security or correctness.
• Design, build and own backend services in Java, from the first design discussion through to production support. Clean APIs, sound data models and code that the next engineer can understand.
• Build the platform with a security-first mindset: authentication and authorisation, secrets management, encryption in transit and at rest, least-privilege access, and defensive handling of every external input.
• Own the reliability of financial workflows. Idempotency, reconciliation, safe retries, clear failure states and audit trails for anything that touches a balance, a loan or a fund movement.
• Shape our AWS infrastructure and how we run it: infrastructure as code, sensible network boundaries, observability, alerting and incident response you would be happy to be paged by.
• Integrate with external partners, including the financial businesses that build on our platform, and make those integrations resilient to the ways third parties fail.
• Contribute to our security and compliance posture, working with the team on threat modelling, code review, vulnerability management and the controls that keep our ISO 27001 and SOC 2 commitments real rather than on paper.
• Raise the engineering bar around you through code review, design documents and the occasional well-argued disagreement.

You will do well here if you care about building systems that are correct, secure and quietly dependable, and you like understanding the domain well enough to get them right.

Skills

• An AI-first approach to engineering, with demonstrable experience in spec-driven development powered by the latest AI models, both in your professional work and in your own passion projects. You can show us how you turn a clear specification into working, tested software with AI agents, and you have a point of view on where that works brilliantly and where it needs a careful human eye.
• Around 5 to 8 years of professional backend engineering experience in Java. We care about what you have built, run and fixed in production.
• Strong, hands-on experience with the Spring framework is essential. You know Spring Boot well, along with the wider ecosystem such as Spring Security, Spring Data and transaction management, and you understand what the framework is doing for you underneath.
• Solid, hands-on AWS experience. You have designed and operated services there, not just deployed to it, and you are comfortable with IAM, networking, managed databases, queues and infrastructure as code (Terraform, CDK or CloudFormation).
• A security-first approach to engineering. You think about threat models, access control and data protection as part of the design, and you have practical experience with things like OAuth/OIDC, secrets management, encryption and secure SDLC practices.
• Solid database experience is essential, including running relational databases on Amazon RDS (PostgreSQL or MySQL). You write good SQL, design schemas with care, understand indexing, query performance and migrations, and know transactions, consistency and concurrency well enough to reason about money.
• Experience with distributed systems patterns: event-driven architectures, messaging, idempotent processing and recovering gracefully from partial failure.
• Experience in financial services, lending, payments or another regulated environment is highly desirable. Familiarity with loan lifecycles, ledgers, reconciliation or credit products is a real plus.
• Experience with a digital asset platform, a tokenised credit engine or blockchain is not required. We will teach you how our digital asset platform and tokenised credit engine work. Bring an open mind, a head for numbers and an appetite for the detail.

Behaviours & Attributes

• AI-first: reaches for the latest AI models as a natural part of how they work, keeps up as the tools change, and stays accountable for everything that ships.
• Ownership: treats the services they build as theirs, in production as much as in development, and raises problems early.
• Security-minded: considers how something could be misused or fail before it ships, and builds the safeguards in rather than bolting them on.
• Problem solver: gets curious about how something actually functions and finds a smarter route through it.
• Pragmatic: balances rigour with momentum, knows where correctness is non-negotiable and where a simpler solution is good enough.
• Curious and open-minded: genuinely interested in how things work, including the parts of our digital asset platform, tokenised credit engine and finance that are new to them, and happy to be persuaded by a better idea.

Why Block Earner?

• An AI-first engineering team, where building with the latest AI models and coding agents is part of everyday work, not a side experiment.
• A roadmap with real ambition behind it: new products in build, a plan that runs well beyond the next quarter, and much of it genuinely original work in a category still being defined.
• Engineering problems you will not find elsewhere, at the intersection of credit, traditional finance and blockchain infrastructure.
• Learn from the best, from our digital asset and DeFi veteran founders, and build a career in the emerging Web3 and blockchain industry.
• A competitive package including equity options in the company you help build.
• Flexible working hours and hybrid work options.
• This role suits someone who enjoys building new things, finds the unknown energising, and wants the pace of a startup where the ambition is high and the path is still being drawn.

We're better together

We are a small, culturally diverse team, and we know that different perspectives make our product better. If you meet most of what is listed here, we would still like to hear from you.

Apply for this role

Write to us with your resume at careers@blockearner.com.au