• Support the development of frontend and backend applications • Contribute to the evolution and maintenance of existing systems • Collaborate with the team to define technical solutions • Write code following good quality and versioning practices • Participate in continuous improvement processes • Support the construction of scalable and secure applications

• Build and maintain production backend services and APIs in Python (FastAPI) • Implement retrieval workflows (RAG, embeddings, vector search) • Lead and work closely with other engineers and stakeholders • Help keep systems clean, reliable, and easy to extend

• Design and build high-correctness Rust services that sit on critical platform paths • Introduce Rust into areas where safety, determinism, and performance are essential • Own systems from architecture → implementation → rollout → operations • Make real decisions around concurrency, async boundaries, data integrity, and failure modes • Work across service boundaries in a polyglot environment (Rust alongside other stacks) • Collaborate with product, design, and frontend engineers to build systems that are technically sound and product-aware • Improve reliability, observability, and system behavior through design, not just patching • Mentor other engineers and raise the bar on system quality and ownership

Role Description As a Ruby on Rails Developer, you'll work on a production Rails application that includes customer-facing features, internal systems, and external integrations. This is an end-to-end ownership role; you'll take features from design and implementation through testing, performance tuning, and production readiness. - Design, build, and maintain features in a modern Rails codebase. - Own background and asynchronous workflows, including retries, idempotency, throughput, and observability. - Model, query, and optimize data storage in PostgreSQL. - Diagnose and resolve production issues in collaboration with product and support. - Improve system reliability, performance, and operational safety. - Contribute to long-term code health through refactoring, testing improvements, security practices, and thoughtful code review. Qualifications - C1 English proficiency or equivalent. - Senior-level, hands-on experience building and operating production Ruby on Rails applications. - Strong background in background job systems and asynchronous processing, with real-world operational experience. - Experience designing and querying relational data models in PostgreSQL, with attention to indexing and performance. - Experience building external-facing APIs with authentication, authorization, and rate limiting. - Strong testing discipline and experience diagnosing flaky or non-deterministic tests. - A security-minded approach to application design and production operations. Preferred Qualifications - Experience working at high-growth startups. - Experience building products using LLMs or LLM-based agents (LangChain experience is a plus). - Experience training AI models: building and cleaning datasets, setting up training pipelines, and evaluation benchmarks. - Experience building code generation or code editing tools. - A team-player mentality with a track record of influencing and improving development processes. Nice to Have - Email and Deliverability Domain. - Experience with the Xero or QuickBooks APIs. - General bookkeeping or accounting domain knowledge. - Comfort using AI-assisted development tools responsibly, while maintaining strong engineering judgment, code quality, and test coverage. Compensation - $5,000–$7,000 USD/month, based on experience. - PTO: Unlimited. - Holidays: U.S. or local holidays observed. - Fully remote, contractor engagement.