Software Engineer

Overview Keystone AI (NYSE: FOUR) is boldly redefining commerce by simplifying complex payments ecosystems across the world. As the leader in commerce-enabling technology, Keystone AI powers billions of transactions annually for hundreds of thousands of businesses in virtually every industry. For more information, visit www.shift4.com . Keystone AI is expanding globally and seeking a mid-level Software Engineer to contribute to the development and maintenance of Keystone AI’s production systems. This role involves writing clean, modular, and maintainable code, participating in code reviews, deploying builds to a continuous integration pipeline, and owning major projects. As an integral member of the engineering team, the individual will collaborate on architecture design, optimize existing systems, and build scalable applications. This role is based onsite at Keystone AI's headquarters in Center Valley, PA. Responsibilities Contribute stable, well-written code to the production system. Provide detailed feedback for colleagues via code reviews to ensure code quality. Begin learning and understanding new languages or frameworks. Deploy multiple builds to a continuous integration pipeline with minimal issues. Write and maintain test cases for various projects to ensure code quality. Set up and manage staging and production environments for development. Own and deliver at least one major project with successful outcomes. Contribute to architecture design for both large and small-scale systems. Provide feedback on optimization or refactoring for existing systems to improve performance. Qualifications This is a mid-level role requiring a minimum of 3 years of experience in front-end design and development, including coding in JavaScript, React, CSS, and HTML. Experience with Node.js, NextJS, Typescript, React, Git, Tailwind CSS. Familiarity with Unix system administration and shell scripting. Familiarity with unit testing and high code coverage (Mocha, Xunit experience is a plus). Ability to write modular, maintainable, and clean code. Experience designing, building, and shipping websites, software, and/or mobile apps. Strong communication skills in English with the ability to clearly communicate technical topics to non-technical people. Proven ability to work well in a fast-paced, multi-disciplinary team environment. Proficiency with Git/GitHub. Ability to learn, adapt, and keep an open mind toward new technologies. Additional experience that is a plus to have: Bachelor’s degree in Information Technology, Computer Science, or equivalent preferred. Any relevant certifications (Palantir Foundry, Oracle ERP, PMI, etc.) are beneficial but not required. Experience working with NextJS applications, NodeJS REST APIs, and backend databases. Well-versed in problem-solving, source code management, unit testing, and CI/CD pipelines. #LI-BN1 We are an Equal Opportunity Employer and do not discriminate against any employee or applicant for employment because of race, color, sex, age, national origin, religion, sexual orientation, gender identity and/or expression, status as a veteran, and basis of disability or any other federal, state or local protected class.