Senior Backend Engineer

Job Title: Senior Backend Engineer (Search & AI Infrastructure)

Location: New Delhi & Seoul, South Korea (Gangnam/Pangyo) / Remote Friendly

Industry: Travel & Hospitality Tech

Role Overview

As a Senior Backend Engineer, you will be responsible for the core architecture that powers our next-generation travel discovery engine. You won't just be CRUD-ing data; you will be building high-performance systems that understand traveler intent. You will bridge the gap between traditional databases and modern LLM-driven architectures to provide hyper-personalized itineraries, real-time availability, and "human-like" travel assistance.

Key Responsibilities

Architect Hybrid Search Systems: Design and maintain systems using Reverse Indexes (Elasticsearch/Solr) for exact matching (e.g., "Hotel in Jeju") and Vector Databases (Milvus/Pinecone/Weaviate) for semantic discovery (e.g., "Cozy places near the beach for a solo writer").

Build RAG Pipelines: Develop and optimize Retrieval-Augmented Generation (RAG) workflows to ground our AI agents in real-time travel data, ensuring recommendations are factually accurate and up-to-date.

Graph-Based Personalization: Leverage Graph Databases (Neo4j/ArangoDB) to map complex relationships between users, destinations, local attractions, and transit hubs.

Optimize Embeddings: Implement and fine-tune Embedding Algorithms to transform unstructured travel content (reviews, blogs, images) into searchable high-dimensional vectors.

Engineering for Performance: Tackle the "Context Switching" challenge within LLM callsminimizing latency and managing token windows to ensure a fluid user experience even during complex multi-step travel planning.

Scalable API Design: Build robust, concurrent backend services (Go, Java, or Python) capable of handling the high-traffic surges typical of Korean holiday seasons (Chuseok, Seollal).

Technical Requirements

Core Backend: 5+ years of experience with high-concurrency languages (Go, Java, or Node.js).

Search & Retrieval: Deep understanding of Inverted/Reverse Indexes and how to tune BM25 or Lucene-based search.

Vector & Graph: Hands-on experience with Vector Databases and Graph Theory (specifically for recommendation engines or knowledge graphs).

AI/ML Integration: Proven track record of deploying RAG systems and working with LLM orchestration frameworks like LangChain or LlamaIndex.

Data Science Lite: Proficiency in Embedding Algos (Sentence-Transformers, OpenAI embeddings) and understanding how to evaluate retrieval quality (NDCG, Recall@K).

Infrastructure: Experience with Cloud-native environments (AWS/GCP), Kubernetes, and distributed caching (Redis).

Preferred Qualifications

Experience in the travel/OTA (Online Travel Agency) sector.

Familiarity with the Korean tech ecosystem (Naver Cloud, Kakao APIs).

Contributions to open-source search or AI projects.

Strong interest in Context Engineeringmanaging how AI retains state across long user conversations.

Why Join Us?

Shape the Future of K-Tourism: Help millions of global travelers navigate South Koreas hidden gems.

Deep Tech Culture: We prioritize engineering excellence over "quick fixes."

Competitive Package: Top-tier salary, stock options, and "Work from Anywhere" weeks.