Mid-level Backend Developer

Description

Job Summary: We are seeking a Mid-level Software Engineer (Backend) to develop and evolve resilient, scalable, and secure services within our payment platform, with a focus on Domain-Driven Design and high-impact engineering. Key Highlights: 1. Working at the heart of an architecturally evolving payment platform. 2. Developing highly available and fault-tolerant backend services. 3. Collaborating on architectural decisions and fostering a high-impact engineering culture. Greenn is a Brazilian payment facilitator (sub-acquirer) focused on digital products. We connect content creators, infopreneurs, and platforms to checkout, payment gateway, and payment-splitting solutions that process millions of transactions. Here, technology is the core of the business — and every line of code directly impacts the lives of thousands of digital entrepreneurs across Brazil. We are currently undergoing full architectural evolution, modernizing our ecosystem using Domain-Driven Design, Event Storming, Strategic Domain Design (SDD), context-driven engineering, and living documentation. If you seek real challenges in a fintech environment with startup pace and scale-level impact, this is the place. **THE CHALLENGE** We are looking for a mid-level backend software engineer with a growth mindset. You will work at the heart of our payment platform — designing, building, and evolving services that must be resilient, scalable, and secure. More than writing code, we expect you to deeply understand the business domain and translate complexity into elegant solutions. We value sound programming practices, especially a strong testing culture. We are building a high-impact, high-performance engineering culture. **YOUR RESPONSIBILITIES** * Develop, test, and maintain highly available and fault-tolerant backend services within the payment ecosystem. * Actively participate in architectural decisions, proposing solutions that balance technical quality and delivery pragmatism. * Collaborate with tech leads to build robust feature-delivery roadmaps, thinking long-term and adhering to best practices. * Ensure quality through automated testing, rigorous code reviews, and CI/CD practices. * Ensure delivered artifacts are automatically and transparently monitored, enabling clear visibility into what has been shipped. * Design and evolve internal and external RESTful APIs with a focus on security and developer experience. * Contribute to engineering culture: technical documentation, Architecture Decision Records (ADRs), pair programming, and mentoring less-experienced developers. * Participate in on-call rotations and incident response as needed. **WHAT WE EXPECT FROM YOU** * Minimum of 3 years of solid backend development experience focused on high-scale web applications. * Experience with PHP (Laravel) as the primary language — familiarity with its ecosystem and best practices. * Knowledge of software architecture: design patterns, SOLID principles, Clean Architecture, hexagonal architecture or ports-and-adapters, unit testing. * Experience with relational databases (MySQL/PostgreSQL) and non-relational databases (Redis, MongoDB or similar). * Experience with distributed systems: message queues (RabbitMQ, SQS, Kafka), distributed caching, asynchronous communication. * Experience with containers (Docker), CI/CD pipelines, and cloud environments (AWS preferred). * Familiarity with observability practices: structured logging, metrics, distributed tracing. * Ability to deeply understand the business context and make data-driven decisions. * Clear and effective communication with cross-functional teams. **NICE-TO-HAVE** * Experience in the payments domain, fintechs, or sub-acquiring. * Experience with Domain-Driven Design (DDD), Event Storming, and domain modeling. * Knowledge of integrations with payment gateways, Pix, registered bank slips (boleto), and receivables advance. * Experience with API versioning, OpenAPI/Swagger, and OAuth 2.0. * Open-source contributions or active participation in the technology community. * Experience with Vue.js or modern frontend frameworks (not your primary responsibility, but helpful).