Senior Python Backend Engineer, Financial Systems

Accountabilities:

• • Build and deploy production-grade Python services, AI agents, and MCP servers supporting complex platform workflows, including tool orchestration, context management, and model routing.
  • Develop and maintain the integration backbone connecting payments, identity, e-signature, real-time data, and other critical third-party services.
  • Design and evolve rules engines and configuration runtimes that enable customers to create and launch new products with minimal engineering intervention.
  • Develop migration and data-import systems capable of moving entire companies onto the platform while maintaining data integrity and supporting zero-loss requirements.
  • Build and scale multi-tenant batch-processing systems handling financially critical workloads, including settlement runs, document pipelines, reconciliation processes, and asynchronous workers.
  • Design and maintain public APIs that serve the broader customer ecosystem, ensuring reliable contracts and supporting AI agents as first-class API consumers.
  • Develop and maintain financial systems covering billing, payouts, commissions, refunds, and other transaction and accounting workflows.
  • Build reliable services capable of operating at the latency and scale required for live financial decisions and high-volume processing.
  • Apply agentic AI coding tools deliberately throughout the development lifecycle to accelerate implementation, testing, debugging, architecture, and delivery.
  • Contribute to the evolution of engineering practices, including AI-assisted development, automated testing, specification-driven development, and multi-agent workflows.
  • Collaborate effectively across technical and product contexts while maintaining high standards for system reliability, security, scalability, and financial accuracy.

  Requirements:

  • Bachelor’s degree or higher in Computer Science or a related technical discipline.
  • 5+ years of professional experience developing web applications and backend systems with Python, particularly in financial systems or financial modules.
  • 3+ years of experience working with SQL databases such as MySQL or PostgreSQL, including data modeling and complex data processing.
  • 3+ years of experience developing SaaS products and cloud-based solutions.
  • 3+ years of hands-on experience with Django or another modern Python web framework.
  • 2+ years of proven experience building and consuming APIs supporting financial transactions.
  • Advanced mathematical capabilities relevant to financial modeling, algorithms, data processing, and transaction systems.
  • Professional experience with Docker and AWS-based cloud environments.
  • Hands-on familiarity with frontend technologies such as React or Vue.js.
  • Daily, intentional use of agentic AI development tools such as Claude, Cursor, or Codex.
  • Demonstrated ability to direct AI agents through complex, multi-file, long-horizon engineering tasks.
  • Strong understanding of backend architecture, API design, distributed systems, and production SaaS environments.
  • Excellent written and verbal communication skills, with the ability to collaborate effectively in a fully remote environment.
  • Experience working in a scaling startup, fintech or financial services environment is a strong advantage.
  • Experience with specification-driven development, AI-generated testing, scaffolding, or architecture is desirable.
  • Experience building production AI agents or multi-step LLM workflows using LangChain, LangGraph, or equivalent orchestration frameworks is a plus.
  • Familiarity with multi-agent development workflows, including Agent Teams, parallel agent orchestration, or comparable approaches, is advantageous.

  Benefits:

  • Fully remote position for candidates located in Brazil or Argentina.
  • Long-term independent contractor engagement.
  • Opportunity to work at the forefront of AI-assisted software engineering.
  • Hands-on exposure to modern AI development tools and agentic workflows, including Claude, Codex, Cursor, Copilot, LangChain, LangGraph, LangFuse, OpenRouter, and FastMCP.
  • Work on complex financial infrastructure where reliability, scalability, and data accuracy directly impact real-world transactions.
  • Opportunity to build production AI agents and intelligent systems rather than working solely on experimental prototypes.
  • High-autonomy engineering environment with significant ownership over architecture, implementation, and technical outcomes.
  • Exposure to a modern technology stack including Python, MySQL, AWS, and cloud-native SaaS infrastructure.
  • Opportunity to contribute to a rapidly evolving engineering culture centered on AI-driven productivity and continuous innovation.
  • Collaborative environment focused on community, integrity, resilience, and measurable impact.