We are looking for a **Senior Fullstack Developer** to work at a growing **fintech**, focused on payment solutions and digital services. This professional will be responsible for **developing, maintaining, and evolving critical systems**, ensuring **technical quality, security, scalability**, and an **excellent user experience** for internal and external customers. They may also serve as a **technical reference (Tech Lead)** on strategic projects. ### **Responsibilities** * Develop applications using **TypeScript, Node.js, React.js, React Native, PHP**, and related technologies. * Ensure code quality through **automated testing**, **code reviews**, and sound engineering practices. * Participate in alignment meetings with **Product Owners, QAs, and developers**, ensuring clarity of requirements and technical impacts. * Analyze requests, propose **technical solutions**, support prioritization, and help organize the development schedule. * Perform **production deployments**, including versioning, configurations, releases, and post-release validations. * Maintain and evolve existing systems by applying fixes, updates, and new features. * Act as a **mentor / Tech Lead**, supporting less experienced developers. * Provide **technical support** to internal and external customers when required. * Contribute to the **continuous improvement** of processes, architecture, and agile practices. ### **Mandatory Requirements** * Solid experience in **fintechs, digital banks, or payment institutions**. * **4 to 5 years** of experience as a Fullstack Developer. * Proficiency in **TypeScript, Node.js, React.js, React Native, and PHP**. * Knowledge of **HTML, CSS, and JavaScript**. * Experience with front-end frameworks (**React, Angular, or Vue.js**). * Experience in back-end development (Node.js or languages such as **Python, Java, or C#**). * Solid knowledge of **SQL and/or NoSQL databases**. * Experience with **agile methodologies** (Scrum, Kanban). * Completed undergraduate degree in **Computer Science, Software Engineering, or related fields**. ### **Preferred Qualifications** * Experience with **mobile app publishing** (App Store and Google Play). * Prior experience in **payment methods**. * **Intermediate English**.