We are seeking an immediate Senior Software Developer (RQ10880) to join the Ministry of Public and Business Service Delivery and Procurement in an onsite role at 222 Jarvis St, Toronto, ON . This position will focus on Java‑based large‑scale web‑application development, RESTful APIs, microservices, security‑gateway integration, and Azure DevOps for enterprise‑scale public‑sector systems. The developer will translate technical specifications into robust, secure, and maintainable multi‑client web applications aligned with OPS standards. Senior Software Developer – RQ10880 Client: Ministry of Public and Business Service Delivery and Procurement Work Location: 222 Jarvis St, Toronto, ON – Onsite (5 days onsite) Estimated Start Date: April 13, 2026 Estimated End Date: October 30, 2026 Business Days: 120 Extension: Probable after initial mandate Hours: 7.25 hours per day Security Level: No Clearance Required About the Role Senior Software Developer responsible for designing, developing, testing, and maintaining large‑scale, multi‑client web applications using Java, RESTful APIs, microservices, and Oracle/SQL databases within the Ontario Public Service (OPS) environment. This role will implement secure, scalable, and high‑performance applications integrated with security gateways (JWT, OAuth 2.0, SSL) and Azure DevOps CI/CD pipelines. Key Responsibilities Software Development & Implementation Translate technical systems specifications into working, tested applications. Develop detailed programming specifications and write code for data‑driven, multi‑client web applications. Conduct unit testing, integration testing, and debugging of applications. Resolve and troubleshoot technical problems during implementation, conversion, migration, and post‑implementation. Provide post‑implementation support and technical troubleshooting. RESTful API & Microservices Design and develop RESTful APIs and web services for enterprise‑scale applications. Implement microservices architecture emphasizing extensibility, maintainability, and scalability. Ensure secure, high‑performance API integrations with front‑end, middleware, and database layers. Security & Protocols Implement security gateways and protocols (e.g., JWT, OAuth 2.0, SSL certificates) for secure authentication and data exchange. Ensure application security and data integrity in compliance with OPS and industry standards. Database & Middleware Integration Develop and maintain Java‑based applications integrated with Oracle and SQL databases. Use relational and hierarchical database technologies for data modeling and querying. Work with middleware and gateways for enterprise‑system integration. Development Methodologies & Tools Use Azure DevOps for CI/CD pipelines, source control, and agile development. Apply Agile methodologies and structured development practices (design, code, test, debug, document). Use object‑oriented coding practices, design patterns, refactoring, and clean‑code principles. Stakeholder Collaboration & Documentation Elicit and document requirements from business stakeholders and subject‑matter experts. Conduct design‑walkthrough sessions with project teams. Provide user and system documentation as required. Ensure compliance with AODA (Accessibility for Ontarians with Disabilities Act) standards where applicable. Experience & Skill Set Requirements Core Skills & Experience (40%) 10+ years as a designer and developer of large‑scale multi‑client web applications. 10+ years of hands‑on Java development with Oracle or SQL databases. 5+ years of RESTful API and RESTful web‑services development. Experience with microservices architecture and core architecture principles. Experience with programming Internet‑ready applications. Experience with Rapid Application Development (RAD) methodologies. Experience using Azure DevOps for CI/CD and project management. Technical Skills & Experience (35%) Knowledge and experience with security gateways and protocols (JWT, OAuth 2.0, SSL certificates). Solid understanding of Agile methodologies and SCRUM practices. Strong object‑oriented programming skills, including design patterns, refactoring, and clean code. Experience with relational and hierarchical databases. Experience with communications protocols and information retrieval using query languages. Soft Skills (20%) Strong communication skills (written and verbal). Ability to conceptualize new approaches and present innovative solutions. Strong team‑collaboration skills and interpersonal relations. Strong problem‑solving and analytical skills. Ability to work under pressure with aggressive timelines. Public‑Sector Experience (5%) Familiarity with OPS Development standards and processes (nice to have). Deliverables Large‑scale web applications built on Java, RESTful APIs, and microservices. Secure, scalable, and maintainable software solutions integrated with Oracle/SQL databases. API‑documentation and technical documentation for applications. Test‑artifacts and bug‑resolution reports. Migration and conversion scripts for enterprise‑system integrations. How To Apply Submit by 10:00 AM EST, Tuesday, March 31, 2026 to: Mandatory Submission Documents Updated Resume in Word format References Expected hourly rate Visa Status LinkedIn ID Note Applications without mandatory documents cannot be processed. Email is the best way to reach the recruitment team. #J-18808-Ljbffr