Job Benefit

  • Attractive salary, annual review, and bonus
  • Thoroughly develop your skills and drive your career path faster.
  • Health care Insurance & social insurance
  • Free in-house snacks, coffee. Happy hour every month
  • Regular team building activities and company trips
  • Parking fee and lunch support
  • Sports activities support
  • Have the chances to work with various products & new technologies
  • With extensive training from senior members, you will learn new things every day
  • Professional and motivated team. Youthful and friendly colleagues

Job Description

Location: Ho Chi Minh City, Vietnam
Work Mode: Contractor | Hybrid Full-time (on-site 1–2 days/week or as required)
English Requirement: B2+ (Good communication)
Duration: 12 months (ASAP Start)

Role Overview

We are seeking a highly experienced Lead Backend Engineer to architect and implement the core backend systems for Felix AI – an innovative EdTech platform leveraging AI to deliver real-time, personalized tutoring. This role is central to building scalable, secure, low-latency systems on Google Cloud Platform, integrating advanced AI services (Gemini, Vertex AI, ADK), and supporting real-time interactions via WebSockets and audio streaming.

Key Responsibilities

  • Design, implement, and scale backend services on GCP with a focus on performance, resilience, observability, and low-latency for real-time communication.

  • Develop RESTful APIs using FastAPI (OpenAPI 3.0 compliant) and efficient Firestore data models.

  • Integrate and orchestrate ADK-based pedagogical agents on Vertex AI, define toolkits (FunctionTools, BaseTools), and manage agent context/state.

  • Implement Gemini Pro/Flash/Live APIs, including streaming logic, configuration handling, and prompt engineering for optimal AI performance.

  • Architect and operate a real-time communication layer over WebSockets (Python) with secure, performant audio (PCM) streaming.

  • Manage distributed session state using Redis (Memorystore).

  • Collaborate with iOS engineer for API/WebSocket contracts and integration.

  • Work with the Full-Stack/DevOps engineer on infrastructure, CI/CD, monitoring, and backend optimization.

  • Contribute to mentoring, code reviews, documentation, and architectural decisions.

Job Requirement

Required Qualifications

  • 7–10+ years in backend engineering, with 5+ years building scalable, distributed, real-time systems.

  • Expert in Python, FastAPI, WebSocket development (including TLS/WSS).

  • Strong experience with GCP (Cloud Run, Firestore, Memorystore, Pub/Sub, Vertex AI).

  • Proficient in integrating LLM APIs (Gemini preferred); experience with ADK or equivalent frameworks (LangChain, LangGraph).

  • Hands-on experience building RAG systems (ideal in educational context).

  • Familiarity with prompt engineering, distributed systems, performance tuning.

Preferred Qualifications

  • Technical leadership experience in AI or EdTech projects.

  • GCP certifications (Cloud Developer or Cloud Architect).

Key Performance Indicators (KPIs)

  • API p95 response time < 500ms (excluding network latency)

  • 99.9% backend uptime

  • Complete and accurate OpenAPI documentation (>95%)

  • Successful agent integration and delivery aligned with roadmap

  • Load-tested scalability to target concurrency thresholds