Python Developer

Only W2

Onsite Position - Only Local Candidates

Job Description:


Seeking a Principal Engineer for our Card Services Technology organization. You will own the application architecture of our card network platforms - designing, building, and evolving the Python-based services that power Chase's credit and debit card processing. You'll write production code, set engineering standards, and be accountable for the technical quality of software that processes billions of transactions annually.

Responsibilities

• Architect and develop Python microservices and APIs integrating with Visa, Mastercard, and debit networks (Interlink, Pulse, NYCE, STAR)
• Own application design across core domains: authorization, clearing, settlement, dispute management, and fraud
• Define data models, event schemas, and API contracts across card processing platforms
• Lead architecture reviews and produce ADRs for new capabilities and modernization efforts
• Build internal frameworks, libraries, and SDKs used across card technology teams
• Establish Python engineering standards - code structure, testing, CI/CD, observability, and API design
• Drive decomposition of legacy and mainframe-adjacent systems into clean service-oriented architectures
• Mentor staff and senior engineers on design patterns and software craftsmanship

Required Qualifications

• 10+ years of software engineering; 5+ years at principal-level or above
• Expert Python: FastAPI, asyncio, Pydantic, SQLAlchemy, pytest
• Strong application architecture background - microservices, event-driven design, DDD, clean/hexagonal architecture
• Solid understanding of card network processing: authorization flows, ISO 8583, clearing, settlement, chargebacks
• Experience building high-throughput, low-latency distributed systems in production
• Proficiency with Kafka or equivalent async messaging patterns
• Strong written and verbal communication; able to align technical and business stakeholders

Preferred Qualifications

• Card network certification experience (Visa, Mastercard, PIN debit)
• Familiarity with tokenization (EMVCo), 3-D Secure, or digital wallet integrations
• Cloud development on AWS, GCP, or Azure with Kubernetes/Docker
• Background modernizing legacy payment platforms
• Experience authoring enterprise-level engineering RFCs or technical standards

Tech Stack

• Python • FastAPI • Pydantic • SQLAlchemy • Celery • pytest • Apache Kafka • PostgreSQL • Oracle • Redis • Kubernetes • AWS • Terraform • GitHub Actions • Splunk • Dynatrace