About the business 21st Century Software is the leader in software solutions for the IBM Z platform, which is the platform trusted by most of worldwide finance institutions, healthcare, insurances, retail and governments. We develop and maintain Mainframe-based software products, partnering with leaders in the Z industry, to service our global customer network. You will join a team where collaboration, sharing knowledge and exchanging ideas is key. The Stuttgart office offers an informal atmosphere, and colleagues from various countries, backgrounds, and ages. About the role In this role you will be working with a team of developers writing and maintaining z/OS mainframe software products, focusing on cutting edge development in the areas of disaster recovery and data management. As part of this team, you will be including aspects of modern development methods including playbacks with our business partners, for an enjoyable, varied and challenging position. You will discover a friendly team-focused environment: an inspiring workplace that provides an open and collaborative culture. Strong z/OS and assembler skills and a passion for learning are necessary to accomplish company and personal goals. Required Skills Fluent in English Senior experience in Mainframe (z/OS) development in Assembler. Strong z/OS and I/O internals knowledge. Candidate should be self-organized, have a strong sense of analysis & troubleshooting skills, and ability to take the lead in problem solving and delivery of development items. Strong interpersonal and communication skills. Commitment to learning new technologies as needed. This position requires strong analytical skills, a commitment to teamwork, and a proactive approach to problem-solving. You will play a key role in ensuring our software solutions meet the needs of our clients in critical sectors such as finance, healthcare, and government. Desired Skills Strong knowledge in Storage management, GDPS, Safeguarded Copy, CSM. Systems programming background. Fluency in German