Sr Software Engineer

Powering the world’s payments ecosystemACI powers the payments ecosystem – globally, and you power ACI. You’ll innovate, collaborate, and grow – in an energetic technology culture with decades of proven success. ACIers – in all roles and levels – are truly your colleagues and many are your friends. Our size and reach allow you to see the global impact of your work. You are visible, your talents are valued, and you are empowered to shape the future of payments.As a Sr. Software Engineer in Norcross, GA, you will join a diverse, passionate team, dedicated to powering the world’s payments ecosystem!Position SummaryWe are seeking an experienced Senior Software Engineer to join the MTS Development team responsible for one of the industry's most critical high-value payments platforms. This role will focus on maintaining, enhancing, and modernizing core payment processing capabilities while supporting regulatory mandates, customer commitments, platform resiliency, and long-term product sustainability.The ideal candidate will be a strong software engineer with experience in complex enterprise applications, payment systems, mission-critical production support, and large-scale modernization initiatives.Key ResponsibilitiesDesign, develop, and maintain core MTS platform capabilities.Deliver customer and regulatory commitments including payment network mandates.Participate in production issue resolution and root cause analysis.Support modernization initiatives including 64-bit migration, ISO 20022, structured address, security, and platform enhancement programs.Collaborate with Product Management, Professional Services, Quality Engineering, and Customer Support teams.Act as a technical mentor and support knowledge transfer initiatives.Drive engineering excellence through automation, testing, observability, and quality improvements.Leverage AI-assisted engineering tools to improve productivity and code quality.Required Qualifications8+ years of software development experience.Strong Java and enterprise application development experience.Experience working with large-scale transaction processing platforms.Experience debugging complex production issues.Strong understanding of software architecture, integration patterns, APIs, and database technologies.Experience with secure software development practices.Excellent communication and collaboration skills.Preferred QualificationsPayments industry experience (Fedwire, CHIPS, SWIFT, ISO 20022).Experience supporting Tier-1 financial institutions.Experience with cloud migration and modernization initiatives.Knowledge of high-availability and mission-critical systems.Experience using AI engineering tools such as Copilot, Cursor, Claude, or equivalent.Success MeasuresSuccessful delivery of roadmap and mandate commitments.Reduction in production incidents and resolution time.Increased automated test coverage.Effective knowledge transfer and documentation.Contribution to long-term platform sustainability.Applicants must be currently authorized to work in the United States on a full-time basis. This position does not offer sponsorship for employment visa status or work permit now or in the future.In return for your expertise, we offer opportunities for growth, career development, and a competitive compensation and benefits package—all within an innovative and collaborative work environment.Are you ready to help us transform the payments ecosystem? To learn more about ACI Worldwide, visit our web site at Job ID (Requisition #19608)ACI Worldwide is an AA/EEO employer in the United States, which includes providing equal opportunity for protected veterans and individuals with disabilities, and an EEO employer globally.Important Notice About Recruitment ScamsJob seekers should be aware of ongoing recruitment scams where individuals or organizations impersonate legitimate companies to offer fake job opportunities. These scams often involve requests for personal information, payments, or interviews through unofficial channels. Please be cautious and verify any communications claiming to be from our company ( / @aciworldwide.com). The ACI Worldwide recruitment team will always follow official channels and will never request payment.#LI-LF1#LI-HybridACI Worldwide is a global leader in mission-critical, real-time payments software. Our proven, secure and scalable software solutions enable leading corporations, fintechs and financial disruptors to process and manage digital payments, power omni-commerce payments, present and process bill payments, and manage fraud and risk. We combine our global footprint with a local presence to drive the real-time digital transformation of payments and commerce.Full timePosting Date: 2026-07-23