Senior Fullstack .NET Developer
Confirmed on the employer's own hiring board on Oct 1, 2026. First seen by Alion on Sep 30, 2026. CI&T scores A on the Alion truth index.
We're looking for a Senior Fullstack .NET Developer to maintain and evolve a set of .NET applications. You will be responsible for the entire ecosystem of a specific business line for our client, work closely with the systems/solutions architect, and maintain daily contact with native English-speaking stakeholders.
For this position the candidate must be experienced in leveraging AI on the day-to-day work. It is not only about coding with AI, but creating Skills, Agents, Tooling, etc, that might enhance development workflows and increase the whole team productivity. This will be the most important differentiator among the candidates.
The position has a strong focus on enhancing, modernizing and automating workflows. The candidate must be capable of maintaining CI/CD pipelines, databases, and AWS infrastructure. Experience on migrating to newer .NET Core versions is a huge differential.
The UI of this set of applications are built with Angular and Vue.js, with some Node.js components for backend services.
Responsibilities:
- Maintain and improve existing .NET Core applications.
- Plan and execute .NET Core upgrades and vulnerabilities mitigations.
- Maintain AWS infrastructure: RDS databases, EC2, Fargate, S3, among other services.
- Evolve APIs and work with multiple external/internal integrations.
- Work with containerized applications using Docker.
- Use Bitbucket, CI/CD, and automated tests as part of the delivery workflow.
- Collaborate with stakeholders to discuss and prioritize tasks and clarify requirements.
- Mentor junior developers.
- Improve the team productivity with AI tooling, processes, and automations.
Requirements:
- 5+ years of experience with .NET Core (C#) and web development.
- Proven experience with .NET version migrations/modernizations.
- Strong experience with SQL and PostgreSQL databases.
- Experience with Angular and/or Vue in production environments.
- Experience with AWS services (RDS, EC2, Fargate, S3, etc.).
- Hands-on experience with Node.js for backend services.
- Proficiency with Docker and containerization.
- Experience with relational databases and integrations with third-party APIs.
- Comfortable with Bitbucket/Git and automated testing.
- Fluent English and strong communication/relationship skills.
Nice to Have:
- Experience with Azure cloud platform.
- Knowledge of Strapi CMS.
- React experience.
- Experience with Mailgun or similar email service providers.
- AI Agents Harness.