Senior Full-Stack Engineer (React Native + AI)

Join our team as a Full-Stack Developer and help shape the future of AI-powered language learning!

You’ll be part of a product team building an innovative mobile app that leverages advanced AI technologies to help users master new languages. Your role will be full-stack, covering both frontend (React Native) and backend (Node.js/Nest.js) development. You’ll work on integrating cutting-edge AI tools, optimizing performance, and creating an engaging, intelligent user experience.

Requirements

We’re looking for a Full-Stack Developer who has:

• 5+ years of experience in full-stack development with a strong focus on React Native;
• Proficiency in TypeScript and backend development with Nest.js, Node.js, or Express;
• Experience building and maintaining PostgreSQL databases;
• Hands-on experience integrating AI functionality using OpenAI SDK, Gemini SDK, or Eleven Labs SDK;
• Experience working with Supabase;
• Familiarity with Expo Go for mobile app development;
• Strong understanding of SaaS tools and how to integrate them into modern JavaScript frameworks;
• Knowledge of scripting languages such as Bash, Python, or PowerShell for automating tasks;
• Experience using collaborative tools like Replit and Cursor;
• Upper-intermediate English level (written and spoken).
  
  

Nice To Have

• Previous experience building AI-powered or edtech mobile apps.
  
  

Responsibilities

As a Full-Stack Developer, you will:

• Develop and optimize features for an AI-powered mobile language learning app (iOS & Android) using React Native;
• Build and maintain APIs and backend logic using Nest.js/Node.js/Express;
• Integrate AI-driven features using tools like OpenAI SDK, Gemini SDK, and Eleven Labs SDK;
• Manage and scale PostgreSQL databases for performance and data integrity;
• Collaborate with designers, product owners, and other developers to define and implement new features;
• Automate routine processes to improve team efficiency using scripting tools;
• Ensure the app runs smoothly and efficiently, continuously improving performance and code quality;
• Take ownership of your work, driving improvements and delivering results in a fast-paced environment.
  
  

Description

ABOUT PROJECT

We're building an AI-powered mobile application that helps users learn languages through interactive, smart, and adaptive experiences. The app combines speech, listening, and text-based learning, powered by the latest language models and AI tools to personalize the learning process for each user.

What Will You Get With Kindgeek

We want you to thrive and feel supported:

Professional growth

We support your development with training and certification refunds, regular feedback, and technical reviews.

Benefits Package

Includes 18 working days of fully paid vacation, 10 compensated by 50% sick leaves (without a doctor's note), and study leaves. Long-term employees receive extended health insurance packages from our partners.

Personal growth

Access corporate English classes with 50% reimbursement, an offline library, internal/external training opportunities, and certifications relevant to your role.

Geek community

Stay connected through online/offline clubs (e.g., English, stretching, skiing), volunteer initiatives, and community events — even during challenging times.

Flexibility

Enjoy a hybrid work model – work remotely, from the office, or our Kindgeek London Hub in Lviv (pet-friendly, too!).

We encourage you to apply

At Kindgeek, we welcome applicants of all backgrounds – regardless of nationality, race, gender, marital status, disability, sexual identity, or religion. We proudly support mobilised employees and veterans in continuing their careers and believe in providing equal opportunities for all.