Software Engineer - Backend

Company Description ProcIndex builds AI agents for accounting. Our product automates AP, AR, reconciliation, approvals, and related finance workflows on top of the systems companies already use, including ERPs like NetSuite, SAP, QuickBooks, and Sage. We are AI-first and focused on reliability, auditability, and safe execution in financial workflows.

Role Description This is a backend engineering role on the early team. You’ll work directly with the CTO and CEO to build agents that read messy real-world inputs, reason over ERP and workflow context, call tools and APIs, maintain state, and take controlled actions in production systems. You’ll build core agent infrastructure: tool runtimes, workflow orchestration, integrations, data models, queues, retries, idempotency, evals, observability, permissions, audit trails, and human review loops.

What You’ll Work On - Build agent systems that process unstructured inputs like invoices, emails, PDFs, ERP records, approvals, and reconciliation data - Design tool-calling infrastructure that lets agents safely read from and act through external APIs - Build workflow orchestration for agent execution, retries, review states, side effects, and failure recovery - Build integrations with ERPs, email providers, document systems, and finance tools - Work with TypeScript, Node.js, Fastify, PostgreSQL, Prisma, and modern LLM APIs - Turn ambiguous real-world workflows into reliable product behavior - Own features end to end, from design through production

What Makes This Role Interesting You’ll build agent systems that do real backend work. The core problem is hard: how do you let an AI system read unreliable inputs, call tools, maintain state, recover from failures, and take safe actions through external APIs? You’ll work on agent runtimes, tool execution, workflow orchestration, structured extraction, queues, retries, idempotency, third-party API integrations, evals, observability, permissions, and audit logs. The product surface is finance, but the engineering problem is building reliable agents that operate in production systems. Because this is an early engineering role, you’ll own core architecture from design through production, not just execute isolated tickets.

Qualifications - 2+ years of industry software engineering experience, excluding internships - Strong TypeScript, Node.js, and JavaScript experience - Experience building integrations with third-party APIs - Proficiency with modern web frameworks such as Next.js, React, or Fastify - Familiarity with PostgreSQL and Prisma, or similar ORMs - Excellent problem-solving skills and ability to work independently - Comfortable with ambiguity and fast iteration - Experience with LLMs, agents, skills, MCP, evals, or tool calling - Bachelor’s degree in Computer Science or related field preferred