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# Building AI Applications with LangChain and Node.js


- **Date:** Thursday, Jul 10, 2025
- **Time:** 10:50–11:20 (30 min)
- **Room:** Stage 2
- **Event:** World Congress 2025
- **Tags:** ai, llms, node.js, postgresql, rag

## Recording

[Watch recording](https://www.wearedevelopers.com/videos/1512-building-ai-applications-with-langchain-and-node-js)

## Description

In this session, we'll dive into the process of creating AI applications using the LangChain framework and Node.js. You'll learn how to effectively integrate Large Language Models (LLMs) into your projects, and how to use embeddings to vectorize text-based documents. This embeddings will be stored in a vector database, we will use pgvector, a extension for supporting vectors in PostgreSQL, which is crucial for handling similarity search queries for Retrieval-Augmented Generation (RAG) applications.

## Speaker

### [Julián Duque](https://www.wearedevelopers.com/@julian-duque)

Principal Developer Advocate at Heroku


## Related talks at this congress

- [Create AI-Infused Java Apps with LangChain4j](https://www.wearedevelopers.com/events/world-congress-2025/sessions/605-create-ai-infused) — Daniel Oh, Kevin Dubois
- [AI Agents Graph: Your following tool in your Java AI journey](https://www.wearedevelopers.com/events/world-congress-2025/sessions/904-ai-agents-graph-your) — Alex Soto
- [One AI API to Power Them All](https://www.wearedevelopers.com/events/world-congress-2025/sessions/718-one-ai-api-to-power) — Roberto Carratalá
- [Semantic AI: Why Embeddings Might Matter More Than LLMs](https://www.wearedevelopers.com/events/world-congress-2025/sessions/542-semantic-ai-why) — Christian Weyer