Job Summary: Senior Backend Developer to work for a global technology client, focused on reducing complexity, architectural evolution, and increasing reliability. Key Highlights: 1. Proactive contribution to backend solution development 2. Active contribution to architectural improvements and evolution 3. Collaboration in an agile environment focused on knowledge sharing **Are you curious, collaborative, and passionate about exchanging knowledge while tackling real technical challenges? Then this opportunity is for you!** We are looking for a **Senior Backend Developer** to work with a global technology client present across multiple countries and delivering high-traffic, high-impact digital products. You will join a newly formed team, spun off from a larger structure, operating within a highly complex chat context. This role requires active participation in analysis, proposal, and implementation of improvements, with a focus on reducing complexity, evolving architecture, and enhancing solution reliability. **Responsibilities and Duties** **In your day-to-day work, you will engage in the following activities:** Proactively and autonomously develop backend solutions; Analyze existing architectures, identifying areas for improvement and opportunities for simplification; Develop and evolve backend services with emphasis on scalability, fault tolerance, and high availability; Implement integrations between systems, APIs, and asynchronous workflows; Work with messaging systems, evaluating processing strategies, reprocessing approaches, and delivery guarantees; Integrate via REST APIs, SOAP APIs, and WebHooks; Contribute to observability, monitoring, and system reliability practices; Actively participate in agile ceremonies, technical refinements, and solution design sessions; Collaborate with various technical teams in an agile environment. **Requirements and Qualifications** **Check below what you’ll need to succeed in this opportunity!** **REQUIRED SKILLS** * Java; * Python, with experience in automation, workers, integrations, scripting, observability, and internal tools; * Elixir, with focus on: concurrent, fault-tolerant, and highly available systems; OTP usage (GenServer, Supervisor, ETS); processes and scalability; * Node.js; * Kotlin, for backend service development, messaging integration, performance optimization, and type safety; * Experience with MongoDB; * Experience with PostgreSQL; * Proficiency in SQL; * Development and integration of REST and SOAP APIs; * Implementation and consumption of WebHooks; * RabbitMQ, including: conceptual differences between queues vs logs, consumer groups, ordering and reprocessing; gradual migration strategies (e.g., dual-write/bridge), observability, and DLQ/DLT usage; understanding of delivery guarantees (at-least-once / exactly-once, with realistic expectations); * Kafka; * Experience with Agile methodologies; * Application of SOLID principles. **PREFERRED SKILLS** * Experience with XMPP / Jabber; * Python (automation, workers, integrations, scripting, observability, and internal tools); * Jenkins; * Git and GitLab CI; * Docker; * Kong, including: * Configuration of routes, plugins, authentication, rate limiting, observability, and policies; * Grafana for monitoring and metric visualization. **Additional Information** **Deliver IT will leave its mark on this project—and we invite you to be part of this journey!** We foster a light, relaxed, collaborative, and diverse culture, along with an enriching environment filled with many talented colleagues across various domains and numerous challenges. Here, you’ll find innovative projects, strong connections, and abundant knowledge exchange! All our positions follow the CLT employment model, with a 44-hour weekly schedule. **OUR BENEFITS** * Work Mode: 100% Remote * VA and/or VR (Meal/food allowance) * Well-being Program: psychological support, legal assistance, social support, financial support. * Health Insurance and Dental Plan * Life Insurance * Wellhub * Monthly Workshops * Discount Partnerships: Sucesu, Target Trust, Sesc, Seprorgs * Company Anniversary Bonus * Referral Bonus for Hired Candidates The technology universe is vast—just like our career opportunities and the reasons you should join Deliver IT. Discover and build your future with us. **VALUES WE DELIVER TO YOU** **IT IS TECH** Here, we use technology to strengthen relationships between people and businesses. **IT IS COLLABORATION** Our collaborative spirit fosters a productive, relaxed, transparent, and human-centered environment. **IT IS RESPONSIBILITY** We understand that innovation requires both freedom and autonomy—and responsibility. **IT IS OPPORTUNITIES** We are valued for our capabilities and receive the necessary support to develop our talents.