Senior Java Developer
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.
We at Sigma Software offer the opportunity to influence architectural decisions, work on long-term product development, and collaborate with experienced engineering teams building modern cloud-native solutions.
Customer
Our customer is a leading EdTech company that uses AI and data-driven technologies to personalize learning experiences, optimize user engagement, and improve marketing effectiveness through advanced audience targeting and analytics.
Project
The 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, and real-time event processing.
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
Requirements
- 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
Will be a plus:
- 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