Senior Java Developer

Role Description

Join a project where scalability, resiliency, and real-time communication are at the core of the engineering challenge. We are looking for a Senior Java Developer to help build a high-load multi-channel communications platform used to deliver critical notifications to millions of users worldwide.

As part of Sigma Software, you will work remotely in an international engineering environment and contribute to the development of distributed, event-driven systems with complex delivery pipelines and fault-tolerant architecture.

Project focuses on building a modern multi-channel communications platform capable of delivering critical notifications across email, SMS, voice, and push channels at massive scale. The system supports:

• Automated workflows
• Emergency broadcasts
• Consent management
• Reporting and analytics
• Provider failover strategies
• Real-time event processing

Job Responsibilities:

• Design and implement a scalable event-driven communications platform
• Build highly reliable and fault-tolerant message delivery systems
• Manage large-scale real-time event processing pipelines
• Design and implement multi-channel delivery pipelines across email, SMS, voice, and push channels
• Handle compliance requirements, consent management, and communication policies
• Support emergency and high-priority notification workflows
• Implement provider failover and resiliency strategies to ensure delivery continuity
• Build tracking systems for delivery status, retries, and engagement events
• Design and implement observability, reporting, and analytics infrastructure
• Develop event processing and message orchestration workflows
• Implement provider integrations and external messaging service adapters
• Ensure system scalability, throughput, and performance under high load
• Collaborate with product and engineering teams on communication flows and requirements
• Contribute to architectural decisions and long-term platform evolution
• Ensure operational stability, reliability, and maintainability of the system

Qualifications

• At least 5 years of software development experience
• Strong expertise in Java development
• Experience with distributed systems
• Strong experience with event-driven architectures
• Experience with messaging systems, queues, streams, and brokers
• Experience designing high-scale APIs and backend services
• Strong understanding of system reliability and fault tolerance
• Upper-Intermediate English level

Requirements

• Experience with email or SMS delivery systems
• Experience with telecom or messaging infrastructure
• Experience with marketing automation platforms
• Experience with notification or engagement systems
• Experience with workflow engines
• Experience with compliance-heavy systems, including consent and GDPR-like regulations
• Experience with high-throughput event processing systems
• Experience with cloud-native platforms, preferably GCP

Benefits

• Strong analytical and problem-solving skills
• Ability to work in distributed cross-functional teams
• Proactive approach to ownership and technical decision-making
• Strong communication and collaboration skills
• Ability to work in high-load, fast-paced environments
• Focus on reliability, scalability, and engineering quality