Back-end Engineer - Python

We're looking for a Back-end Engineer with strong Python expertise to join our platform team. You'll build the data pipelines, ML integration layers, and financial computation engines that power our C33 debt lending platform.

This role sits at the intersection of back-end engineering and data infrastructure — you'll work closely with our AI/ML team to bring models into production and build the Python services that handle forecasting, risk calculations, and automated underwriting workflows.

Key Responsibilities

• Build and maintain Python-based microservices for data processing, financial calculations, and ML model serving
• Develop ETL/ELT pipelines connecting Clickhouse, MongoDB, and external data sources
• Create integration layers between Python ML models (Prophet, scikit-learn) and the TypeScript/NestJS platform

Working knowledge with CrewAI 

• Build automated underwriting and credit scoring workflows
• Implement data validation, transformation, and quality monitoring pipelines
• Develop APIs for internal model inference and batch processing jobs
• Collaborate with the AI/ML team to deploy and monitor models in production
• Write robust test suites and ensure reliability of financial computation services

Required Qualifications

• 5+ years of back-end development experience with strong Python proficiency
• Experience building data pipelines and ETL processes at scale
• Solid understanding of SQL (Clickhouse or similar data warehouses) and NoSQL (MongoDB)
• Familiarity with Python data ecosystem (pandas, NumPy, FastAPI or Flask)
• Experience with asynchronous processing, task queues, and scheduled job orchestration
• Understanding of API design principles and service-to-service communication patterns
• Strong knowledge of testing practices for data-intensive applications
• Comfortable working in a polyglot environment alongside TypeScript/Node.js services

Nice to Have

• Experience in FinTech, lending, or financial services
• Familiarity with ML model serving and MLOps practices
• Experience with Prophet, scikit-learn, or similar forecasting/ML libraries
• TypeScript/Node.js knowledge for cross-team collaboration
• Background in financial data processing, reconciliation, or compliance workflows
• Experience with Cloudflare Workers or serverless computing
• Knowledge of KYC/AML data processing and regulatory reporting

Tech Stack Highlights

• Backend: Python
• Databases: Clickhouse, MongoDB, Redis
• AI/ML: Prophet, scikit-learn, OpenAI, Claude
• Cloud Infrastructure: Cloudflare (Workers, R2, Queues), Azure, Kubernetes
• Payments & Banking: Stripe, GoCardless
• Monitoring: New Relic, Sentry

What We Offer

• A competitive and motivating income that recognizes and values your contributions.
• Opportunity to work on cutting-edge AI and FinTech challenges
• Flexible work schedule to promote work-life balance and accommodate your personal needs.
• Embrace a non-corporate and cozy work environment, where collaboration and creativity flourish.
• Modern tech stack with freedom to explore new technologies
• Direct impact on product direction and technical architecture
• Collaborative environment
• Regular team events and offsites
• Ample opportunities for professional growth and development, empowering you to reach new heights in your career.

Interview Process

1. Initial screening (20 minutes)
2. Technical test (90 minutes)
3. Cultural fit interview with leadership (45 minutes)
4. Reference checks and offer

How to Apply

Send your CV and a brief note about why you're excited to work in FinTech to [email protected]

Please include:

• Links to your GitHub/GitLab profile
• Examples of data pipelines or Python services you've built
• Your experience with our tech stack
• What interests you most about FinTech and AI

About Capital 33

Capital 33 is a next-generation merchant bank focused on two core services: capital raising and direct lending for mid-market and large enterprises. We support every stage of corporate growth—from day-to-day working-capital needs to multi-year investment programs—leveraging deep expertise in structured finance, syndicated loans, private debt, and project finance. We're building the future of FinTech by combining cutting-edge artificial intelligence with deep financial expertise to provide startups with the capital they need to grow.

Capital 33 is an equal opportunity employer committed to building a diverse and inclusive team. We welcome applications from all qualified candidates regardless of race, gender, age, religion, identity, or experience.