Freelance Backend Net Developer Jobs in Geneva, IL

We're seeking an experienced Software Engineer to maintain, enhance, and modernize a suite of .NET-based applications while developing new cross-platform, mobile, and distributed systems. This role bridges legacy modernization with next-generation engineering, spanning .NET, Flutter, Go, Docker, Linux, and private-cloud services.

A central component of this position involves integrating several independent internal applications to create a seamless, cohesive ecosystem across operational, logistics, compliance, and internal systems. The role also includes transforming a legacy Windows application into a modernized, forward-compatible software architecture.

The ideal candidate is comfortable working across Microsoft and non-Microsoft stacks, private cloud environments, Linux-based microservices, modern front-end development, and mobile applications. Familiarity with AI-assisted development tools (Cursor, Copilot, etc.) is highly valued to improve both speed and quality.

Key Responsibilities

• Maintain, troubleshoot, refactor/modernize, and enhance existing .NET Framework / .NET Core applications.
• Architect and develop APIs, microservices, event-driven components, and back-end systems for portals, dashboards, and enterprise workflows.
• Build new back-end services using Go, .NET Core, Node.js, or Python for scalability and cross-platform compatibility.
• Build cross-platform mobile and embedded applications using Flutter.
• Develop lightweight, modern web interfaces using JavaScript/TypeScript with a strong focus on UX/UI design principles.
• Integrate internal applications and data flows to improve cohesion across multiple sovereign systems, unifying workflows and reducing operational silos.
• Plan and execute migration and modernization strategies to the organization's private cloud environment.
• Deploy and manage Linux-based services and containerized workloads (Docker).
• Design and manage CI/CD deployments using Docker, GitHub Actions, or GitLab CI.
• Manage relational databases (SQL Server, Postgres, MySQL), including schema design and performance tuning.
• Utilize AI-assisted tools (Cursor AI, GitHub Copilot) to enforce quality and accelerate delivery.
• Collaborate with IT, engineering, and operations teams to ensure seamless integration and interoperability across business systems.
• Participate in Agile ceremonies, structured change workflows, code reviews, and automated testing.

Requirements

Required Qualifications

• 3+ years of hands-on experience with .NET Framework / .NET Core development.
• Experience building cross-platform mobile applications using Flutter (Dart).
• Proficiency with Go or another compiled back-end language (Rust, Java, etc.).
• Practical experience with Linux service deployment, CLI workflows, and diagnostics.
• Solid understanding of Docker and containerization concepts.
• Experience deploying applications into private cloud or on-premises virtualized environments.
• Strong experience with SQL Server; additional experience with Postgres/MySQL is a plus.
• Ability to support and modernize legacy on-premise applications while designing new cloud-hosted replacements.
• Working knowledge of API design, REST, GraphQL, microservices, and distributed systems.
• Hands-on experience with AI-assisted development tools.
• Familiarity with Git, GitHub, Bitbucket, or Atlassian

Preferred Skills

• Experience converting monolithic applications into microservice or container-based architectures.
• CI/CD engineering with GitHub Actions, GitLab CI, or Jenkins.
• Strong UX/UI fundamentals, wireframing, and component-driven design.
• Familiarity with authentication systems (OAuth2, SAML, JWT).
• Exposure to distributed logging and monitoring platforms such as Sentry.
• Experience working with Atlassian tools (Jira, Confluence) and formal change-order or ticket-based development workflows (helpful but not require)
• Background in logistics, ERP, or enterprise operational platforms is a strong plus.

Soft Skills

• Excellent communication and cross-team collaboration abilities.
• Strong analytical and problem-solving mindset.
• Adaptable, self-directed, and eager to adopt new technologies.
• Strong sense of ownership, accountability, and architectural quality.
• Passionate about automation, UX/UI consistency, performance, and clean engineering principles.

Benefits

• 401(K) with company match from Day 1 
• Blue Cross Blue Shield health insurance - medical, dental, vision, prescription 
• Paid vacation, holidays, and personal time 
• Optional life and disability insurance 
• Safety bonuses for clean roadside inspections and safe driving records 
• Paid training, PPE, and late-model, well-maintained trucks 
• Boot reimbursement program 
• Up to $2,400 company contribution to Health Savings Account (HSA)