Founding Backend Engineer

About the Role Join an early-stage fintech team building backend systems for financial integrations, workflow orchestration, and ledger foundations. You will work closely with founders and early customers to prototype solutions, measure their impact, and shape product and engineering practices. What You'll Do Design, build, and operate backend services and public APIs for customers and partners. Develop integrations with financial systems, ERPs, banks, and data sources, including robust authentication, retry, rate-limit, and webhook handling. Build ETL pipelines with data validation, quality controls, and reconciliation logic. Extract, validate, and normalize information from PDFs, XML, emails, and other unstructured sources. Establish observability and operational practices through logs, metrics, alerts, incident response, and on-call readiness. Work with founders and customers to identify problems, prototype quickly, and decide which features to pursue or retire. Apply LLMs in production when there is measurable value, with appropriate guardrails and monitoring. Document architectural decisions and improve engineering standards for testing, quality, and security. What We're Looking For At least 5 years of backend engineering experience delivering and owning production systems end to end. Strong experience with OLTP systems, relational data modeling, REST APIs, and consistency and availability trade-offs. Experience integrating complex external APIs, preferably in financial or ERP contexts. Practical cloud and DevOps skills with AWS or GCP, Docker, CI/CD, and production monitoring. Experience with data pipelines and reconciliation; familiarity with double-entry accounting and ledgers is valuable. Knowledge of event-driven systems such as Kafka, SQS, or webhooks, and workflow tools such as Temporal, Airflow, or Prefect. Comfort with ambiguity, shifting priorities, and close collaboration with customers; fintech, B2B SaaS, or founding-engineer experience is a plus. Compensation & Benefits Annual base salary: $45,000 to $80,000 USD. Visa sponsorship is not available. Location On-site in Brazil.