Senior C# (.NET) Developer to translate and rewrite legacy VB6 code into modern C#/.NET Core for one of our major banking clients- 39194/40210

Senior C# (.NET) Developer to translate and rewrite legacy VB6 code into modern C#/.NET Core for one of our major banking clients- 39194/40210

Location Address: Scarborough/Hybrid- 3 days in office

Contract Duration: ASAP until Oct 31st (Possibility of extension & conversion to FTE)

Schedule Hours: 9am-5pm Monday-Friday - No over time

Story Behind the Need

• Business group: Client Services and Solutions - Support the corporate commercial clients in the cash management space.
• Project details: Customized Solution Platform (previously known as CCXLate) is an in-house developed file translation and reporting platform that enables the Bank to receive unique customer files and transforms them into a file format that our payment systems can process. It also provides data to the customer in a format their systems can process. This includes detailed reporting data to support their reconciliation, cash positioning, investments, etc. The Customized Solution platform reduces the integration work required for clients’ treasury management/enterprise resource platform systems which allows for rapid onboarding of customers and enables faster revenue generation for the Bank. This platform is a key component to our RFP responses, as no other Canadian FI has an equivalent platform.

Typical Day in Role:

• Review existing VB6 application modules to understand current business logic, workflows, and dependencies.
• Translate and rewrite legacy VB6 code into modern C#/.NET Core following current architectural standards and best practices.
• Analyze legacy SQL queries, stored procedures, and data access patterns, then refactor or rebuild them using SQL Server.
• Document legacy functionality and map it to the new technology stack to ensure functional parity during the rewrite.
• Write clean, maintainable, testable C# code that aligns with the new enterprise-wide modernization framework.
• Perform unit testing and assist with integration testing to validate rewritten components behave consistently with the original system.
• Participate in code reviews to ensure quality, consistency, and adherence to modernization guidelines.
• Troubleshoot issues discovered during the rewrite process and propose improvements to enhance performance, reliability, and maintainability.
• Contribute to ongoing documentation of the new system, including technical specifications, migration notes, and updated architecture diagrams.
• Support the team by identifying gaps, risks, or dependencies in the modernization effort and recommending solutions.

Must Have Skills:

• 10+ years of hands-on experience with C# and .Net (framework and/or .NET Core)
• 5+ years of hands-on experience with VB6, including legacy application support and modernization
• 3+ years of strong SQL Server experience (T-SQL, performance tuning, SSMS, SSRS)
• Experience designing enterprise-grade, scalable applications using clean architecture
• Proficiency with development tools such as Visual Studio, Git, Azure DevOps, Bitbucket,

Nice to have requirements

• Hands-on experience with REST APIs, Web Services, and integration patterns
• Experience in financial industry
• Experience with Agile/Scrum methodologies and CI/CD pipelines
• Exposure to ISO 20022 or financial message transformations
• Experience with cloud services and DevOps pipelines

Degrees or certifications:

• Bachelor's degree in computer science, information technology, or a related field (or equivalent work experience).

Best vs average candidate

The ideal candidate is someone with strong experience working on legacy applications and leading modernization efforts. Because this project involves a large scale rewrite, we need someone who has already navigated the complexities of migrating older systems into a modern technology stack. Their background should include hands-on exposure to refactoring legacy code, validating functionality through thorough testing, and ensuring feature parity during the transition. This migration experience is the key indicator that they can step into this role and deliver successfully.

An average candidate would be someone who hasn’t gone through a major migration before. Without that experience, they’re often caught off guard by the unexpected issues that come up when rewriting or modernizing legacy systems. Migrations rarely go exactly as planned, and people who haven’t lived through that tend to struggle when things break, behave differently, or require creative problem solving. Candidates with real migration experience understand that unpredictability is part of the process, and they know how to adapt quickly, troubleshoot on the fly, and keep the project moving forward.

Candidate review and selection:

1st round - hiring manager, architect, and senior manager - 30- 60 min -MS Teams video call or in person is preferred at 2201 Eglinton Ave E Ecosystem 4- previous experience and technical questions.

2nd Panel interview with Architect and Senior manager - 30 mins - Video call - cultural fit and technical skills assessment.