1

Senior Mainframe Developer Jobs in Ontario (NOW HIRING)

Lead discovery and dependency mapping of legacy environments including mainframes, core banking ... Collaborate with application owners and engineering teams on cloud-native modernization and ...

Lead discovery and dependency mapping of legacy environments including mainframes, core banking ... Collaborate with application owners and engineering teams on cloud-native modernization and ...

About the Role We are seeking a Senior Business Systems Analyst to join our team. This role plays a ... Partners with vendors, solution designers, and engineers to align design, API behaviors, data ...

Showing results 41-44

Senior Mainframe Developer information

See Ontario salary details

$29

$49

$71

How much do senior mainframe developer jobs pay per hour?

As of Sep 4, 2026, the average hourly pay for senior mainframe developer in Ontario is $49.29, according to ZipRecruiter salary data. Most workers in this role earn between $42.07 and $56.49 per hour, depending on experience, location, and employer.

What is a senior mainframe developer?

Senior Mainframe Developers are experienced professionals who design, develop, and maintain mainframe systems—large-scale computers used by organizations for critical applications, bulk data processing, and enterprise resource planning. They are proficient in languages like COBOL, JCL, and Assembler, and often work with databases and transaction processing systems. Their responsibilities include troubleshooting system issues, optimizing performance, mentoring junior developers, and ensuring the reliability and security of mainframe operations.

What are some common challenges faced by senior mainframe developers when integrating legacy systems with modern technologies?

Senior Mainframe Developers often encounter challenges when integrating legacy mainframe systems with newer technologies such as cloud platforms, APIs, or microservices. These challenges include ensuring data consistency, maintaining system security, and minimizing downtime during migrations. Collaboration with cross-functional teams, such as infrastructure engineers and application developers, is key to developing seamless integration solutions. Staying up-to-date with modernization tools and best practices can help address these complexities and support the organization's digital transformation goals.

What are the key skills and qualifications needed to thrive as a senior mainframe developer, and why are they important?

To thrive as a Senior Mainframe Developer, you need deep expertise in mainframe programming languages (like COBOL, JCL, and PL/I), systems analysis, and a strong understanding of legacy application architectures, typically supported by a degree in computer science or related experience. Familiarity with tools such as IBM z/OS, DB2, CICS, and version control systems is essential, along with relevant certifications like IBM Certified System Programmer. Excellent problem-solving, communication, and leadership skills help you collaborate effectively and mentor junior developers. These skills are crucial for maintaining mission-critical systems, ensuring reliability, and guiding modernization efforts in complex enterprise environments.

What are the most commonly searched types of Mainframe Developer jobs in Ontario?

The most popular types of Mainframe Developer jobs in Ontario are:

What are popular job titles related to Senior Mainframe Developer jobs in Ontario?

For Senior Mainframe Developer jobs in Ontario, the most frequently searched job titles are:

What job categories do people searching Senior Mainframe Developer jobs in Ontario look for?

The top searched job categories for Senior Mainframe Developer jobs in Ontario are:

What cities in Ontario are hiring for Senior Mainframe Developer jobs?

Cities in Ontario with the most Senior Mainframe Developer job openings:

Infographic showing various Senior Mainframe Developer job openings in Ontario as of August 2026, with employment types broken down into 78% Full Time, 11% Part Time, and 11% Contract. Highlights an 80% Physical, 5% Hybrid, and 15% Remote job distribution, with an average salary of $102,528 per year, or $49.3 per hour.

AWS Cloud Architect

Adastra Corporation

Thornhill, ON • Hybrid

Full-time

Posted 5 days ago


Key responsibilities

  • Design end-to-end AWS architectures for migrating on-premises banking applications, core systems, and data to AWS with minimal disruption to critical financial services

  • Develop detailed migration plans and runbooks aligned with regulatory change-control, business continuity, and disaster recovery requirements

  • Collaborate with application owners and engineering teams on cloud-native modernization and refactoring of core banking, payment, and customer-facing systems


Job description

Overview

AWS CLOUD ARCHITECT

POSITION SUMMARY

We are seeking an experienced AWS Cloud Architect to lead the design and execution of cloud migration initiatives for critical banking systems and infrastructure. The role will focus on architecting secure, resilient, scalable, and audit-ready AWS environments while managing the unique technical, security, and regulatory considerations associated with migrating financial systems from legacy on-premises data centers. The successful candidate will work closely with Risk, Compliance, Information Security, Enterprise Architecture, and application teams to ensure cloud solutions meet regulatory and institutional standards while enabling business continuity and modernization

Primary Location:

Toronto, ON

Work Model:

Hybrid 3-Days Onsite

Employment Type:

Contract

RESPONSIBILITIES

  • Design end-to-end AWS architectures for migrating on-premises banking applications, core systems, and data to AWS with minimal disruption to critical financial services
  • Lead discovery and dependency mapping of legacy environments including mainframes, core banking platforms, databases, and middleware to determine appropriate migration strategies
  • Define and execute migration approaches including rehost, replatform, refactor, and retire
  • Develop detailed migration plans and runbooks aligned with regulatory change-control, business continuity, and disaster recovery requirements
  • Architect AWS landing zones, VPCs, network segmentation, and security controls aligned with banking security and data residency requirements
  • Design and support hybrid connectivity solutions using AWS Direct Connect, VPN, and Storage Gateway
  • Partner with Information Security, Risk, Compliance, and Enterprise Architecture teams to ensure solutions meet regulatory and internal control requirements
  • Define encryption, key management, identity and access management, privileged access, and other security controls appropriate for financial data
  • Develop infrastructure-as-code using Terraform and/or CloudFormation to enable consistent, auditable, and repeatable deployments
  • Produce architecture documentation, control evidence, risk assessments, and other materials required for audits and regulatory examinations
  • Collaborate with application owners and engineering teams on cloud-native modernization and refactoring of core banking, payment, and customer-facing systems
  • Establish cloud cost governance and optimization practices including tagging, chargeback, Reserved Instances, and Savings Plans
  • Provide technical guidance and mentorship to engineering and infrastructure teams on secure AWS architecture patterns
  • Serve as a technical liaison during regulatory examinations, third-party risk assessments, and internal audits related to cloud infrastructure

QUALIFICATIONS, SKILLS & EXPERIENCE

  • Senior-level experience as a Cloud Architect, AWS Cloud Architect, Solutions Architect, or similar role
  • Strong hands-on experience designing and implementing enterprise AWS cloud architectures
  • Proven experience leading large-scale migration of on-premises infrastructure and applications to AWS
  • Strong understanding of AWS services including VPC, IAM, KMS, CloudHSM, Direct Connect, VPN, Storage Gateway, and related networking and security services
  • Experience designing AWS landing zones, network segmentation, secure connectivity, and multi-account cloud environments
  • Strong understanding of hybrid cloud architectures and on-premises to AWS migration strategies
  • Experience with infrastructure-as-code tools such as Terraform and/or AWS CloudFormation
  • Experience with cloud security, encryption, identity and access management, privileged access, and data protection
  • Experience working with enterprise risk, compliance, information security, and architecture teams
  • Strong understanding of business continuity, disaster recovery, change management, and operational resilience
  • Experience creating architecture documentation, migration runbooks, risk assessments, and audit/control evidence
  • Strong understanding of enterprise networking, databases, middleware, and legacy infrastructure
  • Excellent communication and stakeholder management skills with the ability to work across technical and business teams
  • Experience working in regulated environments, preferably financial services or banking

NICE TO HAVE

  • Experience with banking, financial services, or other highly regulated environments
  • Knowledge of financial industry regulatory frameworks such as FFIEC, GLBA, PCI-DSS, SOX, and OCC guidance
  • Experience migrating core banking platforms, payment systems, transaction processing platforms, or customer data environments
  • AWS certifications such as AWS Certified Solutions Architect - Professional or AWS Certified Security - Specialty
  • Experience with AWS Control Tower and enterprise cloud governance
  • Experience with cloud cost management and FinOps practices
  • Experience supporting regulatory examinations, internal audits, or third-party risk assessments
  • Experience mentoring cloud engineering and infrastructure teams
  • Experience with cloud-native modernization and application refactoring

ABOUT ADASTRA

Adastra is a global leader in AI and data-driven transformation, helping organizations lead with artificial intelligence-responsibly, strategically, and at scale. With over 25 years of experience, Adastra empowers enterprise clients to unlock business value through data innovation, operational excellence, and smart customer engagement.

Trusted by some of the world's most prominent brands, Adastra delivers end-to-end solutions grounded in thoughtful strategy, robust governance, and deep technical expertise. From defining vision to ensuring execution, Adastra guides organizations through every stage of their AI, data and cloud journey-building future-ready capabilities and delivering measurable, lasting impact.

Adastra serves clients across key industries including financial services, automotive, manufacturing, technology, media and telecom (TMT), healthcare, retail, and professional services. The company employs more than 2,000 professionals across North America, Europe, and Asia.

EQUAL OPPORTUNITY EMPLOYER

In our commitment to promote fair and equitable treatment of all employees and applicants, Adastra Corporation provides equal employment opportunities for all individuals regardless of age, sex, disability, race, ethnic origin, citizenship, creed, sexual orientation, marital status, or any other ground as described in the Ontario Human Rights Code.  In addition, accommodation will be provided during the hiring process. Adastra Corporation's implementation and support of employment initiatives, encourage diversified labour force participation and equal access to opportunities based on merit and performance.

AI Usage - Our hiring process includes the use of AI-enabled tools to screen applications (e.g., keyword matching, qualification ranking). A human recruiter reviews all AI-generated shortlists to make informed hiring decisions.

There has been an increased instance of fraudulent job offers coming from people posing as Adastra HR employees. Please note that Adastra will never request fees as part of our recruiting process and any emails sent to you that are not from '@adastragrp.com' or '@talent.icims.com' are fraudulent. All employment offers are sent via DocuSign and if you receive an employment offer from a suspicious email and not via DocuSign, it is fraudulent.

Contact careers@adastragrp.com to inquire about jobs at Adastra, to report a suspicious request for money or personal information from external websites or suspicious employment offers.

Employment Type: OTHER