Senior Fullstack Developer

Role Description

Our team is seeking a skilled Senior .NET/Next.js Fullstack Developer to join our development team. The ideal candidate is a senior-level professional with deep expertise in both modern .NET backend development and Next.js/React frontend architecture. You will design, develop, and maintain complex, end-to-end enterprise applications - from scalable RESTful APIs and domain-driven backend services to high-performance, feature-sliced frontend applications using optimal rendering strategies.

This role requires strong ownership of fullstack solutions, including test-driven development, CI/CD pipelines, architectural decision-making, and mentoring across both backend and frontend layers.

Responsibilities

• Design, develop, and maintain robust .NET backend applications and high-performance Next.js frontend applications using current frameworks and best practices.
• Implement comprehensive testing strategies: XUnit + TDD for backend and Jest/React Testing Library/Playwright for frontend.
• Architect scalable fullstack solutions using established design patterns, Domain-Driven Design (DDD), layered architecture, and Feature-Sliced Design (FSD).
• Optimize application performance through strategic use of SSR, SSG, ISR, client-side rendering, query optimization, and caching.
• Design and optimize PostgreSQL database schemas, views, stored procedures, and indexes while integrating via Entity Framework Core.
• Implement and maintain CI/CD pipelines for automated testing and deployment across backend and frontend.
• Lead technical decisions on architecture, state management, rendering strategies, and API-frontend integration.
• Collaborate with cross-functional teams (including UX/UI) to deliver exceptional user experiences and high-quality software.
• Participate in code reviews, enforce coding standards, and mentor junior developers on .NET and Next.js best practices.
• Manage complex application state and dependency injection across both layers (Redux Toolkit/RTK Query, Zustand, InversifyJS patterns).

Qualifications

• 8+ years of professional fullstack development experience with strong expertise in both .NET (C#, .NET 5+ / .NET Core) and Next.js 13+ / React (TypeScript).
• Expert-level proficiency with XUnit + TDD (backend) and Jest/React Testing Library (frontend).
• Strong understanding of CI/CD principles and hands-on implementation experience.
• Comprehensive knowledge of software design patterns (Singleton, Factory, Repository, Strategy, Observer, etc.).
• Proficiency in architectural styles and patterns including Client-Server architecture & RESTful API design, Layered architecture & Domain-Driven Design (DDD), Feature-Sliced Design (FSD) methodology, and Micro-frontend principles.

Requirements

• Advanced PostgreSQL experience: complex query optimization, performance tuning, database design/normalization, views, stored procedures, triggers, and index optimization.
• Proficient with Entity Framework Core (Code-First, Database-First, migrations, performance optimization).
• Advanced proficiency with Redux ecosystem (Redux Toolkit, RTK Query, middleware, selectors, Reselect).
• Extensive experience with Zustand (store composition, persistence, hydration, TypeScript safety).
• Experience with dependency injection and IoC principles (InversifyJS or equivalent frontend DI containers).
• Expert-level TypeScript with advanced type system usage.
• Modern React patterns (Hooks, Context, Suspense, Concurrent Features).
• Experience with version control (Git) in Azure DevOps and GitHub.
• Strong problem-solving, analytical, communication, and collaboration skills.
• Experience working in Agile/Scrum methodologies.
• Strong understanding of web security principles and best practices.

Preferred Qualifications

• Experience with containerization (Docker Compose/Swarm, Kubernetes).
• Knowledge of cloud platforms (Azure, AWS).
• Familiarity with microservices and event-driven architecture (message queues).
• Experience with monorepo management (Nx, Turborepo, or Lerna).
• Background in front-end development for CRM or enterprise applications.
• Knowledge of GraphQL alongside RESTful services and advanced data-fetching strategies.
• Understanding of edge computing, CDN optimization, SEO, Core Web Vitals, and PWA implementation.
• Experience with A/B testing, feature flags, design systems, and component libraries.
• Familiarity with Tailwind CSS, CSS-in-JS, or styled-components.

Benefits

• Real flexibility. Real balance: Competitive PTO + strong health coverage so you can actually disconnect.
• Work that challenges you (in a good way): Global projects. Complex problems. Zero "maintenance-only" roles.
• Build your AI edge: Access to AI-driven projects, upskilling opportunities, and certifications that keep you ahead of the curve.
• A team you'll actually learn from: Collaborate with top-tier engineers across LATAM, Europe & the US.
• Remote-first, no friction: Work where you perform best-with the structure and trust to deliver.
• Grow fast, not just stay busy: Exposure to modern tech, cross-functional teams, and real career paths.