Senior Dotnet Developer

22nd Century Technologies Inc.; Dallas (TX); On-site; USD 120,000 - 170,000; Full time

Job summary

22nd Century Technologies Inc. in Dallas is seeking a Senior .NET Developer to design, build, and modernize mission-critical web applications using the Microsoft stack, including .NET, Azure, Angular, and SQL Server.

You will mentor developers, collaborate with product owners, and help evolve legacy systems toward a cloud-first architecture, with hands-on coding and architectural input across the full stack.

Qualifications

• 6+ years of professional software engineering experience building production web applications.
• Strong proficiency in C# and .NET (Core/5/6/7/8) including RESTful APIs and backend services.
• Hands-on experience with modern front-end frameworks, preferably Angular (v10+), exposure to React.
• Practical experience deploying and running applications in Azure (App Service, Functions, storage).
• Solid understanding of relational databases (SQL Server; Oracle is a plus).
• Experience with CI/CD pipelines using Azure DevOps or GitHub Actions.
• Bachelor's degree in CS/Engineering or related field; or equivalent experience.

Responsibilities

• Design, develop, and maintain backend services and APIs using C#, .NET (Core/6/7/8), and ASP.NET Core in Azure.
• Build and maintain rich front-end applications using Angular and contribute to React components when needed.
• Integrate front-end and back-end systems to deliver secure, reliable web applications.
• Collaborate with product owners and stakeholders to refine requirements and deliverables.
• Implement automated tests and help raise code quality and test coverage.

Skills

Strong collaboration

Mentoring

Communication

Problem solving

Education

Bachelor's degree in computer science, Engineering, or related field; or equivalent experience

Tools

C#

NET

Azure

Angular

SQL Server

ASP.NET Core

Sitefinity CMS

Oracle

GitHub/GitHub Actions

Azure DevOps

React

Azure Functions

Job description

Need Local Candidates only or From Florida

Job title: Senior .NET Developer

Client: State Client

Duration: 1 Year+ extension

Work Arrangement

100 % onsite

Duration

1 year + extension

Description

The client is modernizing the systems that support our riders, employees, and regional partners. We are looking for a Senior Software Engineer to help design, build, and modernize mission-critical web applications and services using the Microsoft stack (.NET, Azure, Angular, SQL Server), while thoughtfully evolving legacy systems (Classic ASP, older .NET, and CMS platforms) into a cloud-first architecture.

In this role, you will act as a hands-on senior engineer: owning technical design, writing production code, mentoring other developers, and collaborating with product owners and business stakeholders across the agency.

Responsibilities

• Design, develop, and maintain backend services and APIs using C#, .NET (Core/6/8), and ASP.NET Core running in Azure.
• Build and maintain rich, responsive front-end applications using Angular (v15+; currently Angular 19) and contribute to React-based components where needed.
• Integrate front-end and back-end systems to deliver secure, reliable, and performant web applications.
• Work with Azure services (App Service, Azure Functions, Durable Functions, storage, and related PaaS offerings) to build cloud-native solutions.
• Design and optimize relational data models, queries, and stored procedures in SQL Server; integrate with Oracle where required.
• Support and gradually modernize legacy applications (Classic ASP, older .NET web apps, Sitefinity 13/15) as part of broader transformation efforts.
• Use AI coding assistants in a "vibe coding" style for rapid prototyping and boilerplate generation, while thoroughly reviewing, testing, and understanding the resulting code before it reaches production.
• Contribute to application and solution architecture, helping choose patterns, tools, and approaches that balance reliability, maintainability, and delivery speed.
• Implement automated tests (unit, integration, and/or end-to-end) and help raise the overall test coverage and quality of the codebase.
• Perform thoughtful code reviews, provide constructive feedback, and help establish and enforce engineering standards and secure SDLC practices.
• Collaborate closely with product owners, business analysts, security, infrastructure, and operations teams to refine requirements and deliver high-quality solutions.
• Use Azure DevOps and GitHub for source control, branching, pull requests, code reviews, and CI/CD pipelines.
• Help troubleshoot and resolve production issues, improve observability (logging, metrics, dashboards), and drive root-cause analysis and follow-up improvements.
• Mentor mid-level and junior engineers, share knowledge, and help grow the overall capability of the team.
• Contribute to technical documentation and internal wiki content so other teams can understand, support, and extend the systems you build.

Qualifications

• 6+ years of professional software engineering experience building production web applications.
• Strong proficiency in C# and .NET (Core/5/6/7/8) including experience building RESTful APIs and backend services.
• Hands-on experience with modern front-end frameworks, preferably Angular (v10+); exposure to React is a plus.
• Practical experience deploying and running applications in Azure (e.g., App Service, Azure Functions, storage, configuration, identity).
• Solid understanding of relational databases (SQL Server required; Oracle nice to have), including schema design, query optimization, and performance troubleshooting.
• Experience with Git-based workflows and CI/CD pipelines using Azure DevOps (or similar tools such as GitHub Actions).
• Working knowledge of secure coding practices (authentication/authorization, protecting secrets, input validation, OWASP Top 10 concepts).
• Proven ability to take loosely defined business problems and turn them into clear technical designs and deliverables.
• Strong communication skills and experience collaborating with both technical and non-technical stakeholders.
• Bachelor's degree in computer science, Engineering, or related field; or equivalent experience.

Preferred qualifications

• Experience in public sector, transportation, or other mission-critical operational environments.
• Experience migrating and modernizing legacy web applications (Classic ASP, older ASP.NET Web Forms or MVC).
• Sitefinity or other .NET-based CMS experience (authoring, customization, or integration).
• Experience with Azure Durable Functions, event-driven architectures, and distributed systems patterns.
• Familiarity with integrating with enterprise systems such as Workday, ServiceNow, or similar platforms.
• Experience building or integrating with chatbots, search, or AI-assisted workflows (e.g., Azure AI Search, Azure OpenAI, or similar).
• Experience with Application Insights or similar monitoring/logging platforms to instrument and observe production systems.
• Comfortable using tools like GitHub Copilot, ChatGPT, or similar AI assistants to accelerate development while maintaining high code quality.
• Prior experience mentoring other engineers, acting as a tech lead, or owning significant systems end-to-end.