Job Summary: OK is seeking a Junior/Mid-level Back End Developer to develop and maintain REST APIs, evolve systems, and participate in technical decisions within a fintech, software, and financial operations environment. Key Highlights: 1. Development and maintenance of REST APIs 2. Contribution to system evolution 3. Participation in technical decisions with the team OK is a B2B credit, collections, and relationship platform designed for companies selling under a recurring revenue model. We operate at the intersection of fintech, software, and financial operations, focusing on accelerated growth and market validation. We are looking for a Junior or Mid-level Back End Developer to work on developing and maintaining REST APIs in an AWS environment, contributing to the evolution of our systems and participating in technical decisions alongside the team. Job Responsibilities: * API Development: Design and maintain APIs (Application Programming Interfaces) that enable communication between the frontend (the part of the application users see and interact with) and the backend. * Database Management: Design, implement, and manage databases where application data is stored. This includes writing efficient queries and ensuring data integrity. * Business Logic: Implement the logic defining how data can be created, stored, and manipulated. This includes implementing rules and processes governing the application’s behavior. * Authentication and Authorization: Implement authentication (verifying user identity) and authorization (controlling access to different parts of the system). * Security: Protect the application against threats such as SQL injection, DDoS attacks, and other security vulnerabilities. * Integration with External Services: Integrate the application with third-party services, such as payment systems, email delivery platforms, etc. * Maintenance and Support: Fix bugs, implement new features, and provide technical support for the existing backend system. **Prerequisites:** * SQL / Postgres * REST * Java 21 * AWS (Lambda, SQS, EventBridge, CloudWatch, API Gateway) * Jdbi3 * Flyway (migrations) * Quarkus **What we offer for this position?** Salary range: R$7,000.00 to R$8,000.00 **Benefits:** Meal Voucher (R$45.00 per day) Birthday Day Off Total Pass Health Insurance (Bradesco) Dental Insurance (Bradesco) Life Insurance Childcare Assistance* Partnerships with Educational Institutions Job Type: Full-time, Permanent CLT Compensation: R$7,000.00 – R$8,000.00 per month Benefits: * Health insurance * Dental insurance * Life insurance * Food allowance * Meal voucher * Transportation voucher Work Location: Hybrid remote work for Barueri, SP