Founding Agentic Engineer

## About Tonifo Tonifo builds AI cost intelligence for finance teams. As organizations expand their spending on large language model providers each quarter, finance and accounting teams have no reliable way to map that spend to general ledger accounts, projects, products, or business units. Tonifo automates this mapping and produces audit-grade records that controllers, finance leaders, and external auditors can rely on with confidence. We are an early-stage company working with design partners and preparing for our first production deployments. Pre-seed funding is closing, and we are building the founding team. ## About the Role We are hiring a Founding Agentic Engineer to own the technical foundation of Tonifo. You will lead the development of two core systems: a classification engine that maps AI provider spend to the general ledger, and an instrumentation engine that discovers and instruments large language model call sites within customer codebases. You will work closely with the founder and design partners to translate customer needs into a reliable, production-grade product. As one of the first members of the team, you will shape Tonifo's engineering culture, architecture, and technical direction. This role offers meaningful equity, broad ownership, and the opportunity to build a product that finance teams will depend on every day. ## A Day in the Life - Design, build, and operate the classification engine, including data ingestion, model selection, evaluation infrastructure, and the feedback loop that incorporates customer corrections. - Build and maintain production-grade data pipelines that synchronize usage and billing data from third-party AI provider APIs, with robust error handling, retry logic, rate limiting, and reconciliation. - Lead the design and implementation of the instrumentation engine, including AST-based code analysis across Python and TypeScript and the security architecture for accessing customer codebases. - Own core infrastructure, including database schema design, multi-tenant data isolation, observability, alerting, and deployment workflows on AWS. - Partner with the founder and design partners to translate customer feedback into product and architectural decisions. - Establish engineering practices, technical standards, and the foundation for the future team. ## Must Have - Five or more years of professional software engineering experience, including production ownership of non-trivial systems. - Strong proficiency in Python, particularly in production backend environments such as FastAPI. - Demonstrated experience designing, shipping, and operating machine learning systems in production. Examples include classification, recommendation, ranking, or retrieval systems that handled real-world data and supported feedback loops over time. - Proven experience building reliable data pipelines that integrate with external APIs, handle failures gracefully, reconcile data, and maintain audit trails. - Working knowledge of AWS service