Senior Backend Engineer

We are building one of Vietnam's most widely used OTT communication platforms, serving nearly 80 million users and processing billions of messages every day. Our system is powered by a large-scale microservices architecture, where reliability, scalability, and performance are non-negotiable. We are looking for a Senior Software Engineer who is not only technically strong but also capable of owning complex systems end-to-end - from design to production - and driving impactful improvements at scale.

What you will do

• Own backend development for Chat features and related conversation experiences;
• Design, develop, and operate scalable services in a high-throughput, low-latency environment;
• Build and maintain messaging APIs used across internal teams and services;
• Work closely with Product Owners and QC to clarify requirements, propose technical solutions, and risk mitigation;
• Ensure high system reliability, performance, and delivery timelines;
• Follow SDLC processes and actively lead debugging, monitoring, and issue tracing;
• Continuously improve system architecture, performance, and observability.

What you will need

• Proven experience with large-scale distributed systems or high-performance platforms;
• Strong understanding of concurrency, asynchronous processing, and parallel systems;
• Proficiency in one or more backend languages: Java, Go, or C/C++;
• Deep knowledge of database systems (SQL and NoSQL);
• Strong understanding of RESTful API design.
• Strong understanding of caching strategies and performance optimization;
• Experience designing scalable systems with advanced data structures;
• Familiarity with networking fundamentals and protocols (HTTP, TCP/IP, UDP, DNS);
• Ability to translate product requirements into clear technical designs and documentation;
• Solid understanding of modern software design principles.

Nice to have

• Experience with modern Java (Java 21+);
• Familiarity with containerization (Docker, Kubernetes);
• Experience with gRPC or Thrift;
• Ability to leverage AI tools effectively in development workflows;
• Awareness of security best practices (OWASP Top 10);