Senior Mainframe Developer

Work Schedule

Environmental Conditions

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 aSenior Mainframe Developer to join our Ottawa-based engineering team supporting the development, enhancement, modernization, and production stability of criticalapplications. 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

• Lead or contribute to modernization and integration initiatives, including impact assessment, interface design, data flow analysis, API or middleware integration, and safe migration strategies

• Participate in and support release planning, deployment, post-production validation, and operational readiness activities

• Participate in an on-call support rotation, including occasional weekends or off-hours

• Ensure adherence to development standards, documentation, security, audit, and compliance requirements

• Collaborate effectively with global teams, including onshore, offshore, business, QA, infrastructure, architecture, support, and cross-functional partners

• Proactively identify risks, dependencies, technical debt, and opportunities to improve system stability, delivery effectiveness, and team capability

Required Qualifications

Bachelor's Degree holder with 8+ years of hands-on Mainframe application development experience

• Strong hands-on expertise in:

  • COBOL

  • CICS

  • JCL

  • VSAM

  • IDMS/DB2

  • SORT utilities

• Excellent understanding of designing and developing applications in Mainframe technologies

• Strong experience supporting both batch and online mainframe applications

• Strong solutioning mindset with ability to design and implement technical solutions

• Demonstrated ownership mindset with the ability to work through ambiguity, proactively identify risks, and drive issues to closure

• Ability to quickly learn complex legacy applications, business processes, data flows, and integration points

• Willing to provide application support as needed and on rotation

• Ability to collaborate with multiple business teams and solve complex issues

• Strong analytical and problem-solving abilities

• Excellent communication, collaboration, and stakeholder-management skills

• Experience with enterprise systems integration

• Knowledge of security best practices and compliance requirements

• Ability to work independently and as part of a distributed team

• Strong team orientation with the ability and willingness to mentor team members and raise overall team capability

Preferred Qualifications

• Exposure to RPG

• Experience with Lotus Notes application development or support

• Understanding of API development, integration, or modernization strategies

• Experience with MQ, middleware, file-transfer patterns, or enterprise integration approaches

• Familiarity with Agile/Scrum methodologies

• Experience working inorder management, fulfillment, supply chain, finance, or other high-volume transactional systems

• Strong experience in production support and incident management

• Experience with tools such as TSO/ISPF, File-AID, Xpediter, Endevor, Changeman, Control-M, CA7, or similar mainframe development and scheduling tools

• Experience working with globally distributed teams, including onshore, offshore, and cross-functional delivery partners

Work Environment

• Location: Ottawa, Canada
• Work Model: Hybrid work model with a combination of onsite and remote work, as defined by team and business needs
• Support Expectations: Participation in a shared on-call rotation, including occasional weekends or off-hours support

What Success Looks Like

The successful candidate will:

• Successfully leads projects and delivers high-quality, scalable, and maintainable solutions

• Provides effective design solutions aligned with business needs, system architecture, and long-term technology direction

• Acts as a technical mentor and go-to person for application knowledge, design guidance, code quality, troubleshooting, and delivery risk management

• Demonstrates strong leadership, ownership and accountability in delivery and production support

• Engages proactively with business stakeholders and adds value in discussions

• Quickly learns complex systems, business processes, and technical dependencies

• Identifies risks, technical debt, and improvement opportunities before they become delivery or production issues

• Continuously learns, explores new approaches, and drives problem-solving initiatives

• Contributes to team success, system stability, and modernization efforts

• Supports a positive, collaborative, and team-first culture by sharing knowledge, mentoring others, and helping the team succeed

Compensation