Senior Mainframe Developer

Work Schedule

Standard (Mon-Fri)

Environmental Conditions

Office

Job Description

As part of the Thermo Fisher Scientific team, you’ll discover meaningful work that makes a positive impact on a global scale. Join our colleagues in bringing our Mission to life every single day to enable our customers to make the world healthier, cleaner and safer. We provide our global teams with the resources needed to achieve individual career goals while helping to take science a step beyond by developing solutions for some of the world’s toughest challenges, like protecting the environment, making sure our food is safe or helping find cures for cancer.

We are seeking a Senior Mainframe Developer to join our Ottawa-based engineering team supporting the development, enhancement, modernization, and production stability of critical applications. This role is ideal for a hands-on mainframe professional who can take ownership of end-to-end delivery, quickly learn complex business and technical domains, lead design discussions, solve production and delivery challenges, and mentor other team members. The successful candidate will bring deep experience with COBOL-based mainframe applications and related technologies, strong analytical and troubleshooting skills, and the ability to partner effectively with business stakeholders, architects, QA, support teams, and global delivery partners. This is a senior role for someone who combines technical depth, strategic solution thinking, accountability, curiosity, and a strong team-first mindset.

Key Responsibilities

• Lead the design, development, testing, implementation, and maintenance of applications using COBOL, CICS, JCL, VSAM, IDMS and SORT utilities

• Own and drive end-to-end delivery of projects, enhancements, defects, and production fixes, ensuring quality, timeliness, and business alignment

• Analyze business requirements and translate them into scalable, maintainable, and reliable technical solutions

• Prepare technical design documents, impact assessments, implementation plans, data flow analysis, and interface specifications

• Collaborate with business stakeholders to understand requirements, identify risks, and propose practical and strategic solutions

• Mentor and guide junior and intermediate developers, conduct code reviews, and promote engineering standards and best practices

• Act as a trusted technical resource for application knowledge, design guidance, code quality, troubleshooting, and delivery risk management

• Lead troubleshooting, root-cause analysis, and resolution of complex production issues, ensuring minimal business impact