Senior Software Engineer

Vaughan - Canada

Monthly Salary: Not Disclosed

Posted on: 16 hours ago

Vacancies: 1 Vacancy

Job Summary

Role Overview

We are seeking a highly skilled Senior Full-Stack Developer with 6 years of experience to lead the digital transformation of our core enterprise applications. You will be responsible for the end-to-end modernization of legacy .NET Framework 4.8 MVC monoliths into high-performance .NET 6 and up microservices and APIs paired with a modern React frontend and hosted on AWS.

This is not a maintenance role; it is a re-engineering role. You will bridge the gap between reliable legacy logic and the future-proof scalability of modern cloud architecture.

Key Responsibilities

Legacy Deconstruction: Analyze 4.8 MVC applications to identify business logic dependencies and integration points for migration.
Architecture Migration: Lead the transition from monolithic architectures to modern design patterns (Microservices Hexagonal or Clean Architecture).
Backend Modernization: Rewrite and refactor legacy C# code 6/8 implementing cross-platform compatibility and improved performance.
Frontend Revolution: Replace Razor/Server-side rendering with a decoupled state-of-the-art React SPA (Single Page Application) using TypeScript and modern state management (Redux Toolkit TanStack Query).
Cloud Orchestration: Design and deploy the modernized stack on AWS leveraging services like Lambda ECS (Fargate) S3 and RDS.
API Design: Build robust secure RESTful APIs that serve as the bridge between the new React frontend and the modernized backend.
CI/CD Implementation: Establish automated pipelines for building testing and deploying both and React components.

Technical Requirements

Backend Expertise

Legacy: Deep understanding of .NET Framework 4.8 MVC and Web API.
Modern: Expert-level proficiency in .NET 6/7/8 and Core.
Language: Advanced C# skills (Generics LINQ Async/Await Dependency Injection).
Database: Experience with SQL Server (T-SQL) and migrating to AWS-managed databases (RDS/Aurora).

Frontend Expertise

React: Strong experience with Functional Components Hooks and modern React patterns.
Languages: JavaScript (ES6) and TypeScript (Required).
Tools: Experience with Vite or Webpack and CSS frameworks (Tailwind Material UI).

Cloud & DevOps (AWS)

Compute: Hands-on experience with AWS Lambda (Serverless) or Amazon ECS/EKS.
Infrastructure: Familiarity with Infrastructure as Code (CloudFormation CDK or Terraform).
Deployment: Building CI/CD pipelines (GitHub Actions).

Preferred Qualifications

Experience using the AWS Porting Assistant or AWS Transform.
Familiarity with containerization (Docker) and orchestration.
Knowledge of Authentication/Authorization standards (OAuth2 OpenID Connect AWS Cognito).
Proven track record of successfully migrating at least one large-scale enterprise application.

We thank you for your interest. Only those selected for an interview will be contacted.

GFL is committed to equal opportunity for all without regard to race religion color national origin citizenship sex sexual orientation gender identity age veteran status disability genetic information or any other protected characteristic. If you are interested in applying for employment and need special assistance or an accommodation to apply for a posted position please contact

This hiring process may utilize machine-based systems to assist in screening and assessing applicants. Final selection decisions are made by our recruitment team.

Required Experience:

Senior IC

Role OverviewWe are seeking a highly skilled Senior Full-Stack Developer with 6 years of experience to lead the digital transformation of our core enterprise applications. You will be responsible for the end-to-end modernization of legacy .NET Framework 4.8 MVC monoliths into high-performance .NET 6...