Senior Ruby on Rails Developer (IoT Integrations)

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Ruby on Rails Developer (IoT Integrations) based in Brazil.

This is a senior engineering opportunity focused on building robust backend systems that connect software applications with physical devices and IoT ecosystems.

You will own backend architecture across multiple projects, setting technical direction for connected-device integrations and cloud communication.

The role combines Ruby on Rails expertise with IoT protocols, high-volume telemetry, real-time processing, and distributed systems.

You will design scalable APIs and data architectures while helping ensure reliable device-to-cloud communication in production environments.

As a technical leader, you will guide engineering standards, mentor developers, and serve as an escalation point for complex cross-layer issues.

You will also collaborate directly with clients, firmware teams, and hardware stakeholders to turn technical requirements into practical delivery plans.

This role is ideal for an experienced engineer who enjoys solving complex infrastructure challenges and working at the intersection of software and connected devices.

Accountabilities

• Own the end-to-end architecture of Ruby on Rails applications and APIs supporting connected-device fleets.
• Design and lead IoT communication layers using MQTT, WebSockets, CoAP, HTTP, or comparable device communication protocols.
• Architect high-volume telemetry ingestion, queuing, event processing, and real-time data pipelines.
• Evaluate and make build-versus-buy decisions involving IoT platforms, message brokers, and data stores, clearly communicating the technical and commercial rationale.
• Design scalable database schemas and infrastructure strategies for time-series, telemetry, and event-heavy workloads.
• Integrate cloud IoT services such as AWS IoT Core or Azure IoT Hub, including device provisioning, certificate management, and over-the-air update workflows.
• Develop maintainable APIs with appropriate versioning, contracts, documentation, and long-term scalability in mind.
• Lead code reviews, establish engineering standards, and promote strong development and testing practices.
• Mentor mid-level and senior engineers through technical guidance, reviews, and knowledge sharing.
• Conduct technical discovery sessions with clients, firmware teams, and hardware stakeholders to understand requirements and define scoped delivery plans.
• Diagnose and resolve complex production issues spanning device, network, infrastructure, and application layers.
• Own technical delivery across multiple concurrent projects while maintaining quality, reliability, and delivery standards.

Requirements

• 8+ years of professional software engineering experience, including at least 6 years of hands-on Ruby on Rails development.
• Proven experience delivering and scaling production-grade IoT integrations.
• Deep knowledge of MQTT or equivalent device messaging protocols and experience operating them at scale.
• Strong API architecture and design skills, including API versioning, contracts, maintainability, and scalability.
• Extensive experience with PostgreSQL or MySQL, including query optimization, indexing, and database performance tuning.
• Strong knowledge of Redis, Sidekiq, and distributed background job architectures.
• Solid automated testing experience using RSpec, Minitest, or comparable frameworks.
• Hands-on experience with Docker, CI/CD pipelines, and production deployment ownership.
• Demonstrated experience leading engineering teams or owning technical delivery across multiple concurrent projects.
• Strong problem-solving and troubleshooting skills across distributed application and device environments.
• Excellent communication skills and the ability to explain complex technical decisions to clients and cross-functional stakeholders.
• Strong ownership, technical judgment, and ability to operate independently in a senior engineering environment.

Benefits

• Opportunity to work on technically challenging IoT and connected-device projects.
• Exposure to Ruby on Rails, cloud IoT platforms, distributed systems, real-time processing, and high-volume data architectures.
• Significant ownership of backend architecture and technical direction across multiple projects.
• Opportunity to work directly with clients, hardware teams, firmware engineers, and other technical stakeholders.
• Leadership opportunities through mentoring, code reviews, and engineering standards.
• Continuous exposure to emerging technologies across IoT, cloud infrastructure, APIs, and distributed systems.
• Remote work opportunity.
• Opportunity to contribute to diverse technology projects spanning startups, SMEs, and enterprise environments.