Back to the Roots With Remix

React Summit

React Summit 2023

Pavlik Kiselev

Building a RAG System in Node.js: Vector Databases, Embeddings & Chunking

Node Congress

Node Congress 2025

Large Language Models (LLMs) are powerful, but they often lack real-time knowledge. Retrieval-Augmented Generation (RAG) bridges this gap by fetching relevant information from external sources before generating responses. In this workshop, we’ll explore how to build an efficient RAG pipeline in Node.js using RSS feeds as a data source. We’ll compare different vector databases (FAISS, pgvector, Elasticsearch), embedding methods, and testing strategies. We’ll also cover the crucial role of chunking—splitting and structuring data effectively for better retrieval performance.Prerequisites- Good understanding of JavaScript or TypeScript- Experience with Node.js and API development- Basic knowledge of databases and LLMs is helpful but not required Agenda📢 Introduction to RAG💻 Demo - Example Application (RAG with RSS Feeds)📕 Vector Databases (FAISS, pgvector, Elasticsearch) &amp; Embeddings🛠️ Chunking Strategies for Better Retrieval🔬 Testing &amp; Evaluating RAG Pipelines (Precision, Recall, Performance)🏊‍♀️ Performance &amp; Optimization Considerations🥟 Summary &amp; Q&amp;A

The modern web would be different without rich client-side applications supported by powerful frameworks: React, Angular, Vue, Lit, and many others. These frameworks rely on client-side JavaScript, which is their core. However, there are other approaches to rendering. One of them (quite old, by the way) is server-side rendering entirely without JavaScript. Let's find out if this is a good idea and how Remix can help us with it? Prerequisites- Good understanding of JavaScript or TypeScript- It would help to have experience with React, Redux, Node.js and writing FrontEnd and BackEnd applications- <a href="https://nodejs.org/en/download/" target="_blank">Preinstall Node.js, npm</a>- We prefer to use VSCode, but also cloud IDEs such as <a href="https://codesandbox.io/" target="_blank">codesandbox </a>(other IDEs are also ok)