Senior Software Engineer (MCP & RAG)

Mastercard Inc.; Dublin; On-site; EUR 90,000 - 130,000; Full time

Job summary

Mastercard is seeking a Senior Software Engineer to lead AI/ML initiatives, building production-grade LLM-driven systems and RAG-based solutions. The role emphasizes scalable architectures, secure data practices, and collaboration across product, engineering, and data teams in a dynamic enterprise environment in Ireland.

You will design and implement knowledge bases with vector search, integrate MCP frameworks, and mentor engineers while ensuring governance and reliability across cloud platforms

Qualifications

• Experience building AI-powered systems using LLMs and RAG.
• Strong Python backend development.
• Experience with LangChain and prompt engineering.
• Knowledge of vector databases and embeddings.
• Experience with AWS and data platforms.

Responsibilities

• Design, develop, and deliver AI-powered solutions using LLMs and RAG.
• Build enterprise knowledge bases with vector search.
• Develop LLM-driven apps with LangChain, prompts, chaining.
• Integrate MCP or equivalent model interaction frameworks.
• Architect scalable, secure cloud and data platform solutions.
• Collaborate with product, engineering, data teams to translate needs.
• Develop robust APIs and microservices for AI apps.
• Ensure compliance with data governance and security.
• Monitor model performance and reliability in production.
• Mentor junior engineers and promote best practices.

Skills

Python

LLMs

Distributed systems

LangChain

Prompt engineering

API design

MCP

Vector databases

Cloud platforms

Education

Bachelor’s or Master’s in CS/AI/Data Science

Tools

AWS

Databricks

Cloudera

Docker

Kubernetes

PGVector

Job description

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

Senior Software Engineer (MCP & RAG)

Overview

The Program Modernization team at MasterCard drives transformation and champions modernization across technology, risk, and service operations. We establish the foundation for scalable programs, resilient systems and control governance that empowers transformation. The mission of the Technology Modernization team is to enable all the Mastercard programs across the organization to thrive in an evolving regulatory environment by fostering a culture of strong technology controls and effective execution. The team designs and delivers innovative, data-driven solutions that fulfill assurance obligations and regulatory requirements by proactively identifying risks, build real-time tools that leverage technology to continuously test and monitor the control environment. These capabilities enables audit-ready compliance portal for inventorying, managing, testing, and evidencing technology controls. Mastercard is committed to driving innovation through advanced technologies and data-driven insights. We are seeking a Lead Engineer to design and deliver scalable, enterprise-grade AI solutions that enhance our digital capabilities and customer experiences. This role will focus on building intelligent, production-ready systems leveraging large language models (LLMs), knowledge bases with vector search, and modern cloud/data platforms, while ensuring alignment with Mastercard’s standards for security, performance, and reliability.

Role & Responsibilities

• Design, develop, and deliver AI-powered solutions leveraging modern architectures, including LLM-based systems and retrieval-augmented generation (RAG)
• Build and maintain enterprise knowledge bases with vector search capabilities, enabling semantic search and intelligent information retrieval
• Develop LLM-driven applications using frameworks such as LangChain, including prompt engineering, chaining, and orchestration patterns
• Implement and integrate solutions leveraging Model Context Protocols (MCP) or equivalent model interaction frameworks
• Architect scalable and secure solutions across cloud and data ecosystems, including AWS, Cloudera, and Databricks
• Collaborate cross-functionally with product, engineering, and data teams to translate business needs into AI-enabled solutions
• Develop and maintain robust APIs and microservices to support AI applications and front-end integrations
• Ensure solutions adhere to Mastercard’s standards for data governance, security, compliance, and operational excellence
• Monitor and optimize model performance, reliability, and scalability in production environments
• Contribute to technical design discussions, mentor junior engineers, and promote engineering best practices

All About You

• Proven experience (5 to 10 years) in software engineering, with strong focus on AI/ML and distributed systems
• Bachelor’s or Master’s degree in Computer Science, Artificial Intelligence, Data Science, or a related discipline
• Strong proficiency in Python, with experience building scalable backend systems
• Experience with Angular or similar frontend frameworks for building user-facing AI applications
• Hands-on experience with LLM frameworks (e.g., LangChain) and building RAG-based systems
• Expertise in designing knowledge bases with vector search and working with embedding models
• Strong experience with cloud platforms, particularly AWS, and familiarity with Cloudera and Databricks ecosystems
• Solid understanding of system design, APIs, and microservices architecture

Preferred Skills

• Experience with Model Context Protocol (MCP) or similar AI orchestration frameworks
• Experience with vector databases such as PGVector, GraphDB
• Familiarity with MLOps practices, including CI/CD pipelines, monitoring, and lifecycle management
• Knowledge of containerization and orchestration (Docker, Kubernetes) Experience working in highly regulated, large-scale enterprise environments

Key Competencies

• Strong problem-solving and analytical thinking
• Ability to operate effectively in a collaborative, fast-paced environment
• Excellent communication and stakeholder engagement skills
• Demonstrated ownership and accountability for end-to-end delivery Commitment to continuous learning and staying current with emerging AI technologies

Corporate Security Responsibility

All activities involving access to Mastercard assets, information, and networks must comply with Mastercard’s security policies and standards. Employees are responsible for maintaining the confidentiality, integrity, and availability of information.

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.

Everyone wants easier ways to pay; we invent them. Checkout lines are slow; we speed them along. Merchants want more sales; we give them data and insights. People need financial access; we connect them. Corporate purchasing is complicated; we make it simple. Commuters are busy; we speed them on their way. Governments need greater efficiencies; we help create them. Small businesses are virtual; we give them access to a world of buyers. Retailers want to fight fraud; we provide the tools.