Haystack

Haystack is an end-to-end framework designed by deepset for building sophisticated LLM applications. In the 2026 market, Haystack distinguishes itself through a rigid component-based architecture that prioritizes modularity and production stability over the rapid-prototyping chaos of earlier frameworks. Its core architecture revolves around Directed Acyclic Graphs (DAGs), allowing developers to build complex pipelines for Retrieval-Augmented Generation (RAG), semantic search, and agentic workflows. Unlike many competitors, Haystack emphasizes 'Enterprise-Grade AI,' offering seamless integration with high-performance document stores like Milvus, Qdrant, and Pinecone, alongside robust evaluation tools. As of 2026, its technical maturity has made it the primary choice for regulated industries requiring clear data lineage and transparent orchestration logic. The framework supports the latest inference paradigms, including NVIDIA NIM integration and advanced metadata filtering, making it highly effective for processing massive, unstructured datasets in private cloud environments. By separating the 'Component' logic from 'Pipeline' execution, it enables high-performance scaling and easier debugging for AI engineering teams.