Principal Software Engineer

Principal Engineer

Our Purpose

Mastercard powers economies and empowers people in 200+ countries and territories worldwide. Together with our customers, we’re helping build a sustainable economy where everyone can prosper. We support a wide range of digital payments choices, making transactions secure, simple, smart and accessible. Our technology and innovation, partnerships and networks combine to deliver a unique set of products and services that help people, businesses and governments realize their greatest potential.

Title and Summary

Principal EngineerOverview
In the milliseconds between when a card is swiped and an approval is returned, Authorization Decisioning delivers more than 20 market-facing services—including industry leading fraud detection—at global scale. Every day, our platforms apply advanced computational intelligence to billions of transactions worldwide, forming part of the critical financial infrastructure for multiple nation states.
As a Principal Software Engineer, you are a technical authority and wayfinder. You provide broad technical leadership across engineering, architecture, product, and operations, shaping the evolution of a highly available, high throughput, globally distributed platform. You are hands-on and influential—experimenting, building, mentoring, and guiding teams from ideation through production and sustained operation.
This role blends deep technical contribution with organizational leadership, driving architectural clarity, engineering excellence, and long term platform resilience.

Role & Scope
• 20–40% hands-on individual contributor, with the remainder focused on technical leadership, architecture, and organizational impact
• Recognized as a technical expert and thought leader within a domain and across teams
• Drives innovation, architectural coherence, and engineering standards across multiple services and programs
• Operates effectively across organizational boundaries, partnering with product, architecture, infrastructure, security, and leadership teams

Key Responsibilities
Technical Leadership & Architecture
• Lead the analysis, design, development, and delivery of complex, enterprise scale software solutions
• Architect and evolve distributed systems, including service interactions, data flows, resiliency patterns, and operational policies
• Define and evangelize reference architectures, design patterns, and run principles (e.g., active/active/active, self healing, auto scaling, poison pill)
• Drive architectural decisions that balance performance, scalability, security, regulatory compliance, cost, and time to market
• Participate in and lead Principal-level architecture reviews, resolving enterprise wide technical and regulatory challenges
Platform & Product Impact
• Collaborate with business and product partners to design and deliver new services, products, and bundles
• Take ownership of the end to end customer experience across a set of services or platforms
• Identify synergies and reuse opportunities across teams to reduce duplication and improve consistency
• Simplify architectures and improve cost/benefit trade-offs across systems and platforms
Organizational Leadership & Influence
• Mentor and coach engineers at all levels; lead Guild initiatives to elevate craftsmanship across the organization
• Consult across teams to guide planning, estimation, and execution for large scale, complex initiatives
• Drive informed trade off discussions to align development capacity with business value drivers (regulatory, security, growth, technical debt)
• Conduct technical interviews and contribute to raising the engineering bar
• Write promotion recommendations based on objective assessment of impact and outcomes
• Represent the organization through internal and external speaking engagements, white papers, and technical blogs
• Actively identify and address siloed behaviors, fostering collaboration and shared ownership

About You
• You have built your career designing and delivering high performance, high transaction volume, globally scalable platforms
• You are known for solving hard, ambiguous problems—and now thrive enabling teams to solve problems no individual can tackle alone
• You balance deep technical expertise with strong judgment, understanding that great software is necessary but not sufficient
• You lead by example: inclusive during ideation, decisive in execution, and present during production crises
• You understand the responsibility of operating critical financial infrastructure and design systems with resilience, security, and compliance at their core
• Your influence is felt not because you assert it, but because of the clarity, trust, and results you consistently deliver

Technical Proficiencies
Architecture & Systems
• Enterprise grade system design, distributed systems, and advanced design patterns (GoF, service to worker, API gateway, intercepting filter, DDD)
• Event driven and data intensive architectures, including Kafka, NATS, MQ, and batch/streaming hybrids
• Deep experience with real time and batch processing, including checkpointing, idempotency, windowing, and schema evolution
• Expertise in in memory distributed caching (e.g., Apache Ignite): data grids, affinity mapping, persistence, eviction, and consistency models
Development & Platforms
• Strong hands on experience with Java, microservices, REST/gRPC, Spring, Axon Framework
• Experience with Go, HTTP/2, streaming, and cloud native architectures
• Secure coding standards and vulnerability management (OWASP, CWE, SEI CERT)
Cloud, DevOps & Data
• Cloud and DevOps platforms: Kubernetes, Docker, Pivotal Cloud Foundry
• CI/CD and automation: Jenkins, Git, Maven, Sonar, Gatling
• Databases and data stores: Oracle, SQL Server, PostgreSQL, Cassandra, Elasticsearch
• Architecture and cost analysis across on prem, hybrid, and public cloud environments

Education
• Required: Bachelor’s degree in Computer Science or a STEM intensive discipline with relevant software engineering experience
• Preferred: Master’s degree in Computer Science or Business, with experience in fintech or payments

Corporate Security Responsibility

All activities involving access to Mastercard assets, information, and networks comes with an inherent risk to the organization and, therefore, it is expected that every person working for, or on behalf of, Mastercard is responsible for information security and must:

• Abide by Mastercard’s security policies and practices;

• Ensure the confidentiality and integrity of the information being accessed;

• Report any suspected information security violation or breach, and

• Complete all periodic mandatory security trainings in accordance with Mastercard’s guidelines.

Experience Level

Senior Level