Ruby on Rails Developer - Mid-Level

We are looking for a Ruby on Rails Developer to join the engineering team of one of our Health clients, one of the largest health benefits platforms providing access to over 29,000 gyms with a presence in more than 2,500 cities in Brazil and Mexico. The company has a solid technical culture, extremely low turnover, and a strong appreciation for internal teams. We are looking for curious, proactive professionals with a business-impact mindset, who have a strong command of Flutter, but are genuinely willing to navigate other technologies in the ecosystem (TypeScript and Flutter), understanding the product from end to end. You will work with a high degree of autonomy, developing and growing in an environment where quality is the direct responsibility of the developer, without separate QA teams: those who develop, test, guarantee, and sustain. What you will do Develop and maintain scalable and resilient RESTful APIs in Ruby on Rails Participate in the entire development cycle: architecture, implementation, automated testing, deployment, and production monitoring Work on the evolution of the core (monolith) as well as microservices fronts and partner integrations (e.g., ERPs, payment gateways, external platforms) Ensure technical quality via Code Review, engineering best practices (Clean Code, SOLID), and team standards Monitor and optimize performance: APM, resource tuning, query analysis and improvement Work in multidisciplinary squads in an agile model (Scrum/Kanban), with c