Senior Software Engineer

Senior Software Engineer (Backend / Full-Stack, AI-Native)About Us We're rethinking enterprise integration for developers and AI agents with a semantic layer: describe the data you need, and the platform gets it - fast, deterministic, secure, self-repairing, auditable, scalable. Already live with banks and financial institutions, and hiring to build the product further. You'll work across our data integration platform and our open-source schema language and ecosystem.What You'll Work On Mostly Kotlin backend, but everyone touches the full stack: the integration platform (streaming pipelines, query execution, API composition, schema resolution, running in production at real financial institutions); our open-source schema language (compiler, type system, query engine, no prior compiler experience needed); our AI agent built on Spring AI (greenfield work orchestrating integrations autonomously); and the frontend (mainly Angular, some React, no specialism required).What We're Looking For Kotlin, or strong modern Java 17+ with a willingness to learn; reactive streams experience (Flux, Mono, coroutines, backpressure); schema/type thinking (OpenAPI, Avro, Protobuf, or similar); event-driven architecture awareness (Kafka or RabbitMQ a plus); strong testing habits; clean, pragmatic code; curiosity and adaptability; full-stack willingness (Angular, React, Vue, or similar); active use of AI-assisted coding tools; strong written English for a distributed, mostly async team; and 5+ years of professional experience shipping production systems.How You'll Need to Work Autonomously, with context and support rather than daily assigned tickets; collaboratively, staying constructive when things break or priorities shift; with genuine customer empathy; openly, sharing your work internally and externally; and at startup pace, where some days are scrappy.Nice to Have Kafka or RabbitMQ experience, Angular/TypeScript specifically, deep Kotlin/JVM ecosystem knowledge, compiler or query engine experience, Spring AI or LLM agent experience, financial services background, or a blog/talks/open-source contributions.What We Offer GBP 70,000-90,000 salary plus early-stage equity, remote-first work (UK-friendly timezones) with occasional onsite office days roughly monthly, a budget for conferences and learning, and a hardware and tooling budget.Oscar Associates (UK) Limited is acting as an Employment Agency in relation to this vacancy.To understand more about what we do with your data please review our privacy policy in the privacy section of the Oscar website.