senior middleware specialist.

We are seeking a highly accomplished Senior Middleware Specialist for an enterprise-level contract opportunity based in Toronto. In this role, you will take on a premier middleware engineering, system integration, and cloud migration capacity, specializing in supporting, optimizing, and modernizing enterprise integration platforms across complex, multi-system environments.

As a senior middleware specialist, you will bridge the gap between legacy on-premises integration servers, modern cloud-native integration services, enterprise application databases, and cross-functional technology teams. Operating within a hybrid work model in Toronto, you will lead the support of existing BizTalk Server integrations, architect modern Azure Logic Apps workflows, configure hybrid cloud adapters, and build continuous integration pipelines. This position demands a technical integration authority with deep .NET, C#, BizTalk Server, and Microsoft Azure experience who can troubleshoot complex messaging workflows, perform performance tuning, and execute seamless cloud transformations.

Location: Toronto, ON

Assignment Type: Hybrid (Minimum 2 days per week onsite)

Contract Duration: 1-year contract (with potential for 1-year extension)

Advantages
Modern Cloud Migration: Drive the transition of legacy enterprise workflows to Azure Integration Services and Azure Logic Apps.

Cutting-Edge Integration Stack: Hands-on engineering across BizTalk Server 2020, Azure Logic Apps, Azure Functions, Azure Service Bus, and API Management.

Enterprise Infrastructure Scope: Design and secure complex integration touchpoints across major enterprise platforms (including SAP, asset management, and operational systems).

Balanced Hybrid Model: Enjoy a flexible working structure combining collaborative onsite days in Toronto with remote work.

Responsibilities
Support, maintain, and optimize enterprise BizTalk Server integration pipelines, orchestrations, schemas, maps, and custom adapters.

Architect, build, deploy, and support Azure Logic Apps (Standard and Consumption) workflows to modernize legacy integrations.

Develop complex data transformations utilizing XML, JSON, XSLT, Liquid templates, C#, and T-SQL stored procedures.

Configure, manage, and secure enterprise integration adapters, including WCF-SAP, WCF-Custom, SFTP, REST, API Management, and hybrid connections.

Monitor integration health, performance metrics, message tracking, end-to-end logging, error handling, and automated retry mechanisms.

Collaborate with technical leads, business stakeholders, and vendor partners to triage defects and resolve cross-system integration issues.

Build, maintain, and manage automated CI/CD release pipelines and Git branching strategies in Azure DevOps.

Execute defect triage, root-cause analysis, performance tuning, and technical support across SIT, UAT, and production cutover phases.

Maintain comprehensive technical documentation, including architecture designs, interface inventories, mapping specifications, and error-handling runbooks.

Provide technical guidance, reusable code templates, and knowledge transfer to internal development teams while adhering to enterprise change governance.

Qualifications
Core Technical & Integration Requirements
Integration Tenure: Minimum 10+ years of dedicated enterprise systems integration experience utilizing .NET, C#, Web API, XML, XSLT, JSON, SQL Server, and T-SQL.

BizTalk Server Expertise: Deep, hands-on experience with BizTalk Server 2020, including orchestrations, pipelines, maps, XSLT schemas, and migration to cloud integration frameworks.

Azure Integration Services: Minimum 4+ years of hands-on experience building, deploying, and supporting Azure Logic Apps workflows.

Azure Cloud Ecosystem: Demonstrated proficiency with Azure Functions, Azure Service Bus, Azure API Management (APIM), Cosmos DB, Azure Data Factory, Storage, and Azure Monitor/Application Insights.

Enterprise Adapters & Protocols: Extensive experience with WCF-Custom, WCF-SAP/SAP .NET Connector, WCF-Web SFTP, REST, BAPIs, IDocs, and enterprise integration patterns.

DevOps & Security: Proficiency with Git version control, Azure DevOps CI/CD pipelines, OAuth2, SSL certificates, Azure Key Vault, Entra ID (Azure AD), and managed identities.

Education: Post-secondary degree or diploma in Computer Science, Computer Engineering, or an equivalent combination of education and experience.

Preferred Certifications & Assets
Microsoft Azure Certification: Microsoft Certified: Azure Developer Associate designation is strongly preferred.

Governance & ITSM: Practical experience working within structured ITIL, change management, and ServiceNow governance processes.

Soft Skills & Delivery Attributes
Analytical Problem Solving: Superior diagnostic and troubleshooting skills to resolve complex distributed messaging failures and performance bottlenecks under operational pressure.

Communication & Collaboration: Excellent verbal and written communication skills with strong interpersonal capabilities to collaborate effectively across cross-functional engineering teams.

Summary
If you're interested in the "Senior Middleware Specialist" role based in Toronto, we encourage you to apply online at
Only qualified candidates will be contacted for the next steps. We look forward to hearing from you!

Randstad Canada is committed to fostering a workforce reflective of all peoples of Canada. As a result, we are committed to developing and implementing strategies to increase the equity, diversity and inclusion within the workplace by examining our internal policies, practices, and systems throughout the entire lifecycle of our workforce, including its recruitment, retention and advancement for all employees. In addition to our deep commitment to respecting human rights, we are dedicated to positive actions to affect change to ensure everyone has full participation in the workforce free from any barriers, systemic or otherwise, especially equity-seeking groups who are usually underrepresented in Canada's workforce, including those who identify as women or non-binary/gender non-conforming; Indigenous or Aboriginal Peoples; persons with disabilities (visible or invisible) and; members of visible minorities, racialized groups and the LGBTQ2+ community.

Randstad Canada is committed to creating and maintaining an inclusive and accessible workplace for all its candidates and employees by supporting their accessibility and accommodation needs throughout the employment lifecycle. We ask that all job applications please identify any accommodation requirements by sending an email to View email address on randstad.com to ensure their ability to fully participate in the interview process.

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