Senior Elixir Backend Engineer

This is a Senior Elixir Backend Engineer role with 8seats based in Sydney, NSW, Australia == 8seats == Role Seniority - senior More about the Senior Elixir Backend Engineer role at 8seats Senior Elixir Backend Engineer The Role We are looking for a Senior Backend Developer with deep expertise in Elixir and the BEAM VM to help us push the boundaries of what real-time messaging can look like at scale. You will own the architecture, performance and reliability of the services that power every conversation on the platform, from Phoenix Channels at the edge to the data layer that keeps everything consistent. This is a systems-level role. You will be responsible for designing high-throughput, low-latency services, shaping our database strategy across Postgres and DynamoDB, and making the infrastructure and security decisions that allow us to grow safely from seed to Series A and beyond. You will work closely with our frontend engineers to refine the data sync patterns that make our offline-first mobile experience feel instant, and partner with leadership on the technical direction of the platform. We are hiring you for your backend depth, but we expect you to grow into the full stack over time. As you settle in, you will develop a working understanding of our React Native and Expo frontend so you can shape end-to-end product behaviour rather than throw contracts over a wall. Who You Are We are looking for an experienced engineer who combines strong technical judgement with a bias to ship. You take quality seriously but you also understand that customer impact comes from features in production, not from theoretical perfection. You move fast, make defensible trade-offs and know when something is good enough to release and improve in flight. Our team values curiosity and a high degree of emotional intelligence. Our most senior engineers have decades of experience and still ask questions every day because they know it is the fastest way to build better systems. You have at least 8 years of professional backend engineering experience, with substantial production time in Elixir and a deep working knowledge of the BEAM VM, OTP and supervision trees.You have designed, shipped and operated real-time systems in production and understand Phoenix Channels, backpressure and the failure modes that come with persistent connections at scale.You have strong system design and architectural instincts honed across multiple production systems, and you think in terms of data flow, failure boundaries and operational behaviour rather than endpoints and modules.You have deep experience designing and managing databases in production, including Postgres (schema design, indexing strategy, query performance, operational health) and DynamoDB (access patterns, partition design, consistency trade-offs).You have strong AWS or equivalent cloud provider experience and have personally owned the infrastructure decisions behind the systems you have shipped.You are an active user of AI development tools who leverages them as an accelerator while maintaining a healthy scepticism about their output and taking full responsibility for the correctness, security and architectural integrity of every line you submit.You have a strong sense for when to build, when to buy and when to defer, and you make those calls in service of shipping product and reaching the next stage of growth.DevOps maturity and a strong sense for technical security are highly desired, including comfort with CI/CD, observability, secrets management and the kinds of decisions that keep a real-time platform safe under load. Our Technical Environment The technologies below describe the environment you will be operating in. Deep backend experience is essential; familiarity with the surrounding stack is helpful but not required, as you will build that context over time. Our backend is written in Elixir and Phoenix Channels to power real-time messaging at scale.We use Postgres as our primary system of record and DynamoDB for workloads where its access patterns and scaling characteristics are the right fit.We run on AWS and treat infrastructure as a first-class part of the product rather than something handed off at the end of a PR.Our frontend is built on React Native and Expo in a monorepo supporting mobile, web and desktop, with WatermelonDB and RxJS on the client and XState v5 for complex flows.We lean on types to keep the compiler doing as much of the heavy lifting as possible, so we can spend our time on logic rather than maintenance. Engineering Excellence in the Age of AI We are looking for engineers who are genuinely fluent with modern AI tooling and who will use it deliberately and effectively to ship product features to customers at a higher standard – not engineers who avoid it, and not engineers who lean on it so heavily they cannot explain their own pull requests. You are a confident daily user of tools like Claude Code, Cursor or equivalents, with a clear point of view on where they accelerate you and where they get in the way.You practise real context engineering and are comfortable with RAG-style and agentic workflows, including extending internal tooling, MCP servers and pipelines that give AI useful access to our code, docs and systems.You use AI aggressively for deterministic and repetitive work, apply healthy scepticism to its output, and are able to stand behind every line in your pull requests. You ensure that the burden of code understanding and verification stays with yourself as the author, not the reviewer. Key Responsibilities Own the architecture, scaling and reliability of our Elixir and Phoenix backend, ensuring it remains performant and maintainable as we expand our feature set towards Series A. Design and evolve our real-time messaging layer using Phoenix Channels, including sync and recovery patterns that hold up under production load.Lead our database strategy across Postgres and DynamoDB, including schema design, access patterns, query performance, migrations and operational health.Architect and operate our AWS infrastructure with a focus on scalability, cost efficiency, observability and security, contributing to CI/CD pipelines and deployment practices that keep delivery fast and safe.Embed technical security thinking into the platform, including authentication, authorisation, data protection, secrets management and threat modelling for a real-time messaging product.Partner with the mobile team to refine the data sync contracts and event flows that power our offline-first client experience.Drive delivery at startup pace, making pragmatic trade-offs that get features into customers’ hands without compromising the integrity of the platform.Participate in high-trust code reviews where you advocate for architectural integrity and the effective use of our functional, declarative programming patterns. The Process Submit Your Application: Send us your CV and a short video to introduce yourself (approx. 2 minutes). Applications that do not include a video will not be considered. Intro Chemistry Session: A 45 minute chat about 8seats and your background. A ‘How You Work’ Session: A technical discussion about your backend architecture experience and your approach to AI integrated workflows. Co-Founder Meet: A final conversation with the 8seats leadership team. Before we jump into the responsibilities of the role. No matter what you come in knowing, you’ll be learning new things all the time and the 8seats team will be there to support your growth. 🟢 Please consider applying even if you don't meet 100% of what’s outlined 🟢 Key Responsibilities Key Strengths Why 8seats is partnering with Hatch on this role. Hatch exists to level the playing field for people as they discover a career that’s right for them. So when you apply you have the chance to show more than just your resume. A Final Note: This is a role with 8seats not with Hatch.