— Empowering Startups

Full-stack Excellence

Explore our comprehensive range of services for launching startups and delivering fast, high-quality web and mobile app solutions. From Symfony backend development to React.js frontend development, DevOps, mobile development with Native or Flutter, and AI/ML expertise, we provide the cutting-edge technologies and expertise needed to bring your ideas to life.

— Symfony

Backend Development

Discover our Symfony backend development services—a popular PHP framework supported by SensioLabs (LOGO). As an official partner, our Symfony-certified developers leverage over 16 years of experience to deliver versatile solutions, from APIs and dashboards to high-performance, scalable architectures.

Versatile development.
We specialize in developing APIs, non-interactive websites, dashboards, marketing websites, and proofs-of-concept using Symfony
Robust architecture.
Our team designs scalable and maintainable backend architectures using Symfony
Official partner.
4xxi is an official partner of SensioLabs, and our developers are Symfony certified
Backend Development

— React.js

Frontend Development

Experience the power of our React.js frontend development services. Our skilled team leverages React.js, a versatile framework for building complex and scalable web applications. With over 7 years of expertise, we make React.js our preferred choice, delivering seamless user interfaces, efficient state management, and streamlined frontend development using UI component libraries like Material-UI or Tailwind UI.

Preferred choice.
React.js is our go-to framework for frontend development in all our web projects
Long-standing expertise.
Our team has been using React.js since its initial release for more than 7 years
State management.
Proficient in implementing efficient state management using Redux or other related libraries
Frontend Development


Experience our DevOps services designed to empower your business. We prioritize scalable and vendor-lock free solutions, leveraging our expertise in AWS, Azure, and Kubernetes. With a focus on open-source technologies like Docker, Kubernetes, and Helm, we excel in infrastructure design, automation, monitoring, security, and seamless CI/CD pipelines for efficient development and deployment.

Scalable solutions
Our DevOps approach prioritizes scalable and vendor-lock free solutions with focus on Open-Source, with expertise in AWS, Azure, and Kubernetes
Infrastructure and automation
We excel in designing and setting up infrastructure, implementing CI/CD, and containerizing existing applications
Security and compliance
We implement robust security measures and ensure compliance with industry standards

— Native or Flutter

Mobile Development

Unlock the full potential of mobile app development with our expertise in native (Kotlin/Swift) and cross-platform (Flutter) solutions. With over a decade of experience, we deliver exceptional mobile apps, prioritizing UI/UX optimization, offline functionality, push notifications, and app performance optimization for seamless user experiences.

Native and cross-platform expertise.
We excel in both native mobile app development (Kotlin/Swift) and cross-platform development using Flutter
Decade of experience.
With over 10 years in mobile app development, we deliver exceptional solutions for various platforms and devices
UI/UX optimization.
Our team focuses on creating intuitive user interfaces and seamless user experiences
Mobile Development

— OpenAI, HuggingFace, LLAMA


Experience the transformative power of our AI/ML services. Automate tasks with advanced Natural Language Processing, leveraging our expertise in language models like OpenAI ChatGPT, LLAMA, Falcon, and HuggingFace's models. From data preprocessing to model training and optimization, we seamlessly integrate and deploy AI/ML solutions for maximum impact.

Model training and optimization
Our experts train and fine-tune AI/ML models to achieve optimal performance
Deployment and integration
We seamlessly integrate AI/ML solutions into existing systems and deploy them for production use
Cutting-edge technologies
We utilize OpenAI ChatGPT, LLAMA, Falcon, and HuggingFace’s models for advanced AI/ML solutions