Work ScheduleStandard (Mon-Fri)Environmental ConditionsOfficeJob DescriptionAs 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 ResponsibilitiesLead the design, development, testing, implementation, and maintenance of applications using COBOL, CICS, JCL, VSAM, IDMS and SORT utilitiesOwn and drive end-to-end delivery of projects, enhancements, defects, and production fixes, ensuring quality, timeliness, and business alignmentAnalyze business requirements and translate them into scalable, maintainable, and reliable technical solutionsPrepare technical design documents, impact assessments, implementation plans, data flow analysis, and interface specificationsCollaborate with business stakeholders to understand requirements, identify risks, and propose practical and strategic solutionsMentor and guide junior and intermediate developers, conduct code reviews, and promote engineering standards and best practicesAct as a trusted technical resource for application knowledge, design guidance, code quality, troubleshooting, and delivery risk managementLead troubleshooting, root-cause analysis, and resolution of complex production issues, ensuring minimal business impactLead or contribute to modernization and integration initiatives, including impact assessment, interface design, data flow analysis, API or middleware integration, and safe migration strategiesParticipate in and support release planning, deployment, post-production validation, and operational readiness activitiesParticipate in an on-call support rotation, including occasional weekends or off-hoursEnsure adherence to development standards, documentation, security, audit, and compliance requirementsCollaborate effectively with global teams, including onshore, offshore, business, QA, infrastructure, architecture, support, and cross-functional partnersProactively identify risks, dependencies, technical debt, and opportunities to improve system stability, delivery effectiveness, and team capabilityRequired QualificationsBachelor's Degree holder with 8+ years of hands-on Mainframe application development experienceStrong hands-on expertise in:COBOLCICSJCLVSAMIDMS/DB2SORT utilitiesExcellent understanding of designing and developing applications in Mainframe technologiesStrong experience supporting both batch and online mainframe applicationsStrong solutioning mindset with ability to design and implement technical solutionsDemonstrated ownership mindset with the ability to work through ambiguity, proactively identify risks, and drive issues to closureAbility to quickly learn complex legacy applications, business processes, data flows, and integration pointsWilling to provide application support as needed and on rotationAbility to collaborate with multiple business teams and solve complex issuesStrong analytical and problem-solving abilitiesExcellent communication, collaboration, and stakeholder-management skillsExperience with enterprise systems integrationKnowledge of security best practices and compliance requirementsAbility to work independently and as part of a distributed teamStrong team orientation with the ability and willingness to mentor team members and raise overall team capabilityPreferred QualificationsExposure to RPGExperience with Lotus Notes application development or supportUnderstanding of API development, integration, or modernization strategiesExperience with MQ, middleware, file-transfer patterns, or enterprise integration approachesFamiliarity with Agile/Scrum methodologiesExperience working in order management, fulfillment, supply chain, finance, or other high-volume transactional systemsStrong experience in production support and incident managementExperience with tools such as TSO/ISPF, File-AID, Xpediter, Endevor, Changeman, Control-M, CA7, or similar mainframe development and scheduling toolsExperience working with globally distributed teams, including onshore, offshore, and cross-functional delivery partnersWork EnvironmentLocation: Ottawa, CanadaWork Model: Hybrid work model with a combination of onsite and remote work, as defined by team and business needsSupport Expectations: Participation in a shared on-call rotation, including occasional weekends or off-hours supportWhat Success Looks LikeThe successful candidate will:Successfully leads projects and delivers high-quality, scalable, and maintainable solutionsProvides effective design solutions aligned with business needs, system architecture, and long-term technology directionActs as a technical mentor and go-to person for application knowledge, design guidance, code quality, troubleshooting, and delivery risk managementDemonstrates strong leadership, ownership and accountability in delivery and production supportEngages proactively with business stakeholders and adds value in discussionsQuickly learns complex systems, business processes, and technical dependenciesIdentifies risks, technical debt, and improvement opportunities before they become delivery or production issuesContinuously learns, explores new approaches, and drives problem-solving initiativesContributes to team success, system stability, and modernization effortsSupports a positive, collaborative, and team-first culture by sharing knowledge, mentoring others, and helping the team succeedCompensationThe estimated annualized pay range for this position in Ontario is $85,500.00–$114,000.00.