Software Engineer II – Front-End (Hybrid)

About the role

Mastercard’s Infrastructure Design Engineering Automation (IDEA) team is seeking a Software Engineer II focused on front‑end development. The position is hybrid, based in O’Fallon, MO, and involves building and enhancing internal web tools that help infrastructure and platform teams create, review, and automate technical designs.

Key responsibilities

• Develop new front‑end features using modern frameworks such as React.
• Refactor existing code to improve clarity, performance, and maintainability.
• Troubleshoot and support production issues as they arise.
• Build responsive, user‑friendly web applications.
• Write unit tests, maintain documentation, and ensure code quality through reviews.
• Collaborate with cross‑functional teams to gather requirements and deliver solutions.
• Participate in design discussions and adopt new development techniques.

Required profile

• Experience in software engineering or application development with a focus on front‑end technologies.
• Foundational knowledge of JavaScript, TypeScript, and React.
• Understanding of HTML, CSS, and API integration.
• Familiarity with version control (Git) and Agile methodologies.
• Comfortable working across the full software development lifecycle.
• Strong problem‑solving abilities and a passion for user‑centric solutions.

Required skills

• JavaScript
• TypeScript
• React
• HTML
• CSS
• Git
• CI/CD pipelines
• API consumption