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# Full-Stack Developer

- **Company:** Latam. Titan Os
- **Location:** Barcelona, Spain
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), HTML5, User Authentication, Automation of Tests, Cascading Style Sheets (CSS), Data Validation, Data Loss, Database Schema, Key Management, PostgreSQL, Node.Js, OAuth, Open Web Application Security, Web Application Security, SQL Databases, Systems Integration, TypeScript, Tailwind, ReactJS, Large Language Models, Database Migration, AI Platforms, Playwright, Integration Frameworks, JestJS
- **Published:** November 11, 2026
- **Apply:** https://www.adzuna.es/details/5960486287

## About the Role

* 2+ years of relevant experience as a full-stack developer with TypeScript, React and Node.js

 * Experience working on production applications, ideally including authentication, database migrations or third-party integrations
 * Experience with Replit, including hosting, deployments, environments and secrets management
 * Working knowledge of PostgreSQL and SQL, and familiarity with Drizzle ORM or a similar TypeScript ORM
 * Understanding of authentication (sessions, JWTs, OAuth, role-based access), ideally with Supabase Auth
 * Good knowledge of HTML5, CSS and Tailwind CSS
 * Experience writing automated tests, ideally with Vitest and Playwright
 * Awareness of web application security basics (OWASP Top 10, secrets handling, dependency updates)
 * Experience integration AI services or LLM APIs into production applications
 * Nice to have: Experience with advertising technology or integrating ad platforms (VAST)

## Description

As a Full-Stack Developer, you will help maintain and grow our advertising platform, which is developed and hosted on Replit. You'll work across the whole stack, from the React front end to the Node.js API and PostgreSQL database. You'll help keep a live production system secure and reliable while delivering new features and integrations., * Design, code, test, maintain and deliver features across the React front end and the Node.js/Express API

 * Build and maintain integrations with third-party APIs and services
 * Investigate and fix production bugs, find the root cause and prevent regressions
 * Maintain authentication and access control built on Supabase
 * Write and run database schema changes and migrations with Drizzle ORM, safely and without data loss
 * Write and maintain automated tests with Vitest, Playwright and Node.js tests
 * Keep the platform secure: dependency updates, secrets management, input validation and access control
 * Manage deployments, environments and releases on Replit
 * Document code and technical decisions so the platform stays easy to maintain