Backend Engineer / 後端工程師

Description

We run one of the highest-traffic social and content platforms in the region: real-time messaging, payments, and media delivery at scale, with a product that has to stay fast and available while we keep growing it.

The Backend team owns the services behind all of that.We're looking for a backend engineer who wants to own features end-to-end, write code the next person can read, and grow into harder problems with us.

You'll ship real things early, with senior engineers and a written growth path to back you up.

Responsibilities

• Build features end-to-end. Work with stakeholders to design, build, test, and ship backend features that hold up under heavy real-world load, with tests, edge-case handling, and observability built in by default.
• Optimization & debugging. Optimize code for performance and cost, and debug complex issues across the service stack in a timely fashion.
• Code review & consistency. Give and receive substantive code reviews, uphold our conventions, and help keep the codebase coherent by reusing existing patterns and leaving things cleaner than you found them.

What You'll Work On

• Scaling our live-streaming platform and the real-time, high-concurrency features behind it as traffic keeps growing.
• Evolving live services without downtime: migrations, refactors, and new components on systems people are using right now.
• Making the system observable and reliable under real load, so problems are caught before users feel them.

Must Have

• At least 1 year building API / backend services in production.
• Good familiarity with Python.
• Ability to provide clear, actionable, and constructive technical feedback in code review and technical discussion.
• Clear communication, and comfortable working with English documentation.
• You own your work: give accurate ETAs, flag blockers early, and follow through to production.
• Strong problem-solving and logical reasoning. You debug by understanding the system, not by guessing.
• A real ownership mindset. We appreciate engineers who are proud of their work and own up to it.
• Genuine motivation to learn and improve.

Nice To Have

• Hands-on with MongoDB or PostgreSQL: schema design, indexing, and query optimization under real traffic.
• Redis for caching and beyond, with a feel for cache invalidation and failure modes.
• Celery or other async / task-queue systems, and the patterns that keep them reliable: idempotency, retries, fan-out.
• Experience with microservice architectures and inter-service communication patterns (REST, async messaging, event-driven); familiarity with gRPC is a plus.
• Solid grounding in the web stack: HTTP / RESTful / TLS / WebSockets / Caching / Containerization.
• Real-time / WebSocket-heavy systems at scale.
• Distributed systems and the trade-offs they force (consistency, availability, partitioning).
• Experience collaborating with cross-team or external engineering partners.

3 Rounds

1. HR Phone Interview

2. Online Assessment 

3. Onsite Interview (whiteboard challenge included), approximately 2~3.5 hrs