Middle+ Full-Stack Engineer (Backend-Oriented)

About the project

The product builds production-grade AI assistants for loan officers, processors, and underwriters. The platform ingests lender documents, classifies and extracts structured data, computes metrics/risk signals, and powers decisioning flows that integrate with existing LOS/CRM systems. Because downstream underwriting decisions depend on the correctness and reliability of backend systems, you will be responsible for building systems where data integrity, security, explainability and uptime directly affect business risk and revenue. You'll work with AI pipelines (LangChain, DSPy), Python services, and a TypeScript core to deliver scalable, auditable features used by enterprise lenders.

Conditions

Involvement: Long-term (3+years) full-time

Team structure: 4 engineers + Tech Lead

Locations: Lisbon (Tech Lead), Slovenia/Slovakia, USA

Stack: Python, Typescript, Next.js, PostgreSQL, AWS, RabbitMQ, Temporal, LangChain, N8N

Key responsibilities

- Design, build and operate backend services powering document ingestion, validation, extraction, and underwriting decisioning.

- Implement and evolve business logic that encodes underwriting rules, exception handling, and scoring pipelines.

- Build and maintain data pipelines (ETL/ELT) for document classification and parameter extraction that integrate with LangChain/DSPy Python components.

- Create robust service integrations between Python AI microservices and the TypeScript/Node.js platform (queues, APIs, events).

- Ensure PostgreSQL schema design, indexing, query optimization and data integrity to support complex analyses and audits.

- Collaborate daily with AI engineers, product, and QA to ship iterative releases and support customer pilots and enterprise integrations.

Must-have skills & experience

- 3+ years commercial backend engineering experience; demonstrable track record of production systems

- Python proficiency: building AI/ML microservices, data pipelines, or backend tools

- Strong in TypeScript / Node.js / Next.js

- Deep experience with PostgreSQL: data modeling, schema migrations, performance tuning and complex queries

- Practical experience with AWS

- Experience integrating message queues and event-driven systems (RabbitMQ or equivalent)

- Direct experience with LangChain, DSPy, prompt pipelines, or LLM orchestration.

- Strong understanding of CI/CD, automated testing, and delivery pipelines

- Proven ability to read, understand, refactor, and improve other people’s code, not just “vibe-coding"

Nice-to-have

- Background in fintech / lending / credit risk or building decisioning engines/business rules

- Experience with OCR/NLP pipelines, document understanding, or leveraging OCR libraries.

Interview & hiring process

- Pre-Screening - 15 min meeting

- Short Intro Call (with tech lead) - up to 30m to present the product and set expectations

- Take-home Case Study - real-world task (expected 2–4 hours)

- Technical Interview (up to 90 minutes) - architecture discussion

- Final Call with founders&leadership - product fit, long-term commitment, offer.