[Job-32277] Senior FullStack Developer (.NET/Javascript/React)
At CI&T, we help large enterprises transform the potential of AI into real business impact with AI Deployment, AI-native execution, and tech-integrated business solutions.
With 30 years of experience in technological transformation, we accelerate innovation with expertise in Agentic SDLC, Application modernization, Data & AI, Martech and Business strategy.
We are 8,000 CI&Ters across more than 25 countries, collaborating to build solutions with real impact. AI is already part of how we work, evolve, and innovate every day.
Job Overview:
We are on the lookout for a passionate and experienced Senior Fullstack Developer to join our engineering team. The ideal candidate will have a strong background in web application development—specifically with .NET Core—and the flexibility and eagerness to adapt to and learn new technologies, including legacy ASP.NET and modern JavaScript frameworks. Additionally, a solid understanding of frontend engineering using React is essential to build, maintain, and evolve high-performance user interfaces.
Key Responsibilities:
- Feature Engineering & Delivery: Design, build, test, and maintain scalable, secure, and resilient fullstack applications using .NET Core and React.
- Security & Best Practices: Actively address security vulnerabilities across both frontend and backend codebases, adhering to modern secure coding standards and OWASP principles.
- Architecture Implementation: Translate architectural guidelines into clean, maintainable, and well-tested code, contributing actionable technical insights to team design discussions.
- Performance Optimization: Continuously monitor, troubleshoot, and optimize application performance, reliability, and backend/frontend interactions.
- AI Tooling & Developer Velocity: Utilize AI tools and agentic workflows (e.g., Claude Code) to accelerate feature delivery, cross-file refactoring, and automated testing.
- Quality & Testing Ownership: Drive test coverage (unit, integration, end-to-end) and enforce robust code quality and CI/CD standards within the development pipeline.
- Team Leadership & Mentorship: Conduct thorough peer code reviews, mentor junior and mid-level developers, and foster a collaborative, continuous-learning culture.
Technical Skills:
- Claude Code Environment Experience: Proficient in using Claude Code via terminal, IDE, and GitHub integrations to accelerate codebase onboarding, cross-file refactoring, and feature delivery.
- Agentic SDLC Experience: Practical experience applying AI agents and AI-driven workflows across the software development life cycle.
- Backend Mastery: Proven experience in backend development with deep expertise in .NET Core (C#) and familiarity with ASP.NET.
- Frontend Engineering: Strong hands-on proficiency in JavaScript, TypeScript, and modern frontend frameworks like React.
- Software Design: Solid understanding of core software development principles (SOLID, DRY) and microservices/monolithic design patterns.
- Data Management: Experience with relational and non-relational databases (e.g., SQL Server, PostgreSQL, MySQL) including query optimization and schema design.
- Cloud & DevOps: Familiarity with cloud computing platforms (especially AWS), containerization, RESTful API design, Git, and automated CI/CD pipelines.
Soft Skills:
Proactive Ownership: Demonstrates initiative by identifying challenges early, proposing pragmatic solutions, and taking end-to-end responsibility with minimal supervision.
- Critical Thinking: Questions underlying assumptions and analyzes problems from foundational concepts up, ensuring deep technical comprehension before taking action.
- Adaptability & Continuous Learning: Eagerness to learn new languages, frameworks, and engineering tools as technical demands evolve.
- Problem Solving: Strong analytical skills with a track record of diagnosing and resolving complex technical issues in production environments.
- Communication & Collaboration: Excellent written and verbal communication skills, with a team-oriented mindset and ability to bridge discussions between product and engineering.
- AI Enthusiasm: A genuine interest in leveraging AI technologies to enhance development efficiency and code quality.
Skills
As published by lever · 20 questions
Basics
Resume/CV, Full name, Pronouns, Email, Phone, Current location, Current company, LinkedIn URL
Short answers (6)
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- What is your salary expectation? Only the numeric value (no currency, text, or benefits)/ Qual é a sua pretensão salarial? Apenas o valor numérico (sem moeda, texto ou benefícios).
- If you feel comfortable, please share your current or last salary and benefits / Caso se sinta confortável, compartilhe seu salário atual ou ultimo e benefícios optional
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- [EN] What is your level of confidence when communicating and collaborating in an English-speaking work environment? optional
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