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Haystack overview and key facts (October 2026)
Open-source framework from Berlin-based deepset for AI agents, RAG pipelines and search, independent of the model provider.
Free
What is Haystack?
Haystack is an open-source Python framework for building production AI applications such as agents, retrieval-augmented generation and semantic search. It gives developers explicit control over retrieval, routing, memory and generation and works with many model providers.
Haystack offers pipelines, agents and ready-made components for retrieval, indexing, tool calling, memory and evaluation. It is maintained by deepset in Berlin, which sells enterprise support and a platform for managed or self-hosted operation. The project names users such as Airbus, Netflix and NVIDIA. The repository had about 26,600 stars and a last push on September 28, 2026.
Haystack AI features and use cases
- Answers questions from company documentsRetrieval pipelines find relevant passages in internal documents and pass them to a language model. Employees get answers grounded in company knowledge rather than general web knowledge.
- Builds agents with toolsHaystack agents call tools, run them concurrently and track token usage. Developers build assistants that look up data or trigger actions in other systems.
- Keeps model choice openPipelines work with OpenAI, Mistral, Anthropic, Hugging Face, Azure OpenAI, Bedrock and local models. Companies can switch to a European or self-hosted model without rebuilding the application.
What sets Haystack apart
- Maintained by a Berlin-based company that offers paid support and an enterprise platform on top of the free framework.
- The enterprise platform runs as a managed cloud service or on your own infrastructure; deepset lists SOC 2 Type II and ISO 27001 for it.
- Collects anonymous usage statistics of pipeline components by default, which can be switched off.
Where Haystack is strongest
Germany Available internationally
Haystack is maintained by deepset, based in Berlin.
Questions to ask before you buy Haystack
Haystack is a developer framework, so plan engineering capacity for building and running applications. Decide which model provider processes documents and whether a self-hosted model is needed for sensitive data. For support and a managed platform, compare deepset's enterprise offers.
Using Haystack in the EU: GDPR and AI Act
- Data locationNot published by the vendor.
- Data processing agreementNot published by the vendor: ask for one (Art. 28 GDPR).
- EU AI ActCheck whether the AI prepares decisions about people. If not, the high-risk rules usually do not apply. The high-risk obligations apply from December 2, 2027 (Digital Omnibus).
General information with sources, not legal advice.
Haystack reviews
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Questions about Haystack
Is Haystack free for commercial use?
Yes. The framework is published under the Apache 2.0 license. Paid options from deepset cover support and a managed or self-hosted enterprise platform.
Can Haystack run without sending data to a US cloud?
Yes. It works with local models and self-hosted databases. deepset's enterprise platform can also be self-hosted.
Which programming language does Haystack use?
Haystack is a Python framework installed with pip as haystack-ai. Docker images are also available.
Haystack update historyno updates yet
No changes recorded for Haystack yet.
Changes the vendor made and confirmed user reports, each checked against the vendor's own pages. We review every tool monthly.
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