# Haystack v3.4.1: what's new, verdict & setup Canonical: https://theagenticweekly.com/tools/haystack · Released: 2026-10-21 · Last verified: 2026-10-25 · Evidence: Tested (smoke test, 2026-10-25, local 3B model (Qwen2.5-3B)) · Vendor: deepset · Official site: https://haystack.deepset.ai/ > Apache-2.0 Python framework for building search, RAG and agent pipelines, maintained by deepset. ## Verdict **Apache-2.0 Python framework for building search, RAG and agent pipelines, maintained by deepset.** Good for: - Production RAG pipelines - Teams that like explicit pipeline components Skip if: - You want a visual builder Tested. Tested 2026-10-25 (America/Chicago). Haystack 3.4.1 passed our one-tool task on a local 3B model: 3 of 3 trials; cold uv install 2.3 s. Test environment: Linux x86_64 virtual machine (Debian 13), 8 vCPU, 15 GiB RAM, no GPU; no vendor account, login or API key. Agent tools were pointed at a local open-weight model (Qwen2.5-3B-Instruct (Q4_K_M) through Ollama 0.40.11), so we tested the tool, not any vendor's hosted models. Not tested: Any vendor-hosted model: everything ran on a local 3B model, so tool-call reliability with frontier models is not measured here; Multi-agent flows, memory, long conversations, streaming, tracing and cloud deployment; Anything beyond one tool and one question; three trials is a smoke test, not a benchmark; Document stores, retrieval pipelines and evaluation. These are smoke tests, not a benchmark. Full log: /tests/haystack. Test scope: - Kind and date: smoke test, 2026-10-25 (America/Chicago). Not a benchmark. - What we ran: Haystack 3.4.1 passed our one-tool task on a local 3B model: 3 of 3 trials; cold uv install 2.3 s. - Model used: Qwen2.5-3B-Instruct (Q4_K_M) through Ollama 0.40.11 - Environment: Linux x86_64 virtual machine (Debian 13), 8 vCPU, 15 GiB RAM, no GPU; no vendor account, login or API key - Not tested: Any vendor-hosted model: everything ran on a local 3B model, so tool-call reliability with frontier models is not measured here; Multi-agent flows, memory, long conversations, streaming, tracing and cloud deployment; Anything beyond one tool and one question; three trials is a smoke test, not a benchmark; Document stores, retrieval pipelines and evaluation. Full test log (commands, versions, raw output): [Haystack 3.4.1: our test log](https://theagenticweekly.com/tests/haystack) Pricing: Official page, dated. Open-source library; costs come from the model APIs you call. (checked 2026-10-25) ## Best for - [Best AI tool for agent building](https://theagenticweekly.com/best/agent-building) (#-): Open-source Python framework for RAG and agent pipelines. ## Key facts Haystack's repository is Apache-2.0 licensed with v3.4.1 tagged Oct 21, 2026 and a push on Oct 24, 2026. - License: Apache-2.0 (per GitHub) - Platforms: Python - Pricing model: Free and open source - Free tier: Free to self-host - Paid plans: None listed for the library - GitHub: deepset-ai/haystack: 26,842 stars on 2026-10-25, last push 2026-10-24 - Latest release we saw: v3.4.1, 2026-10-21 - How to start: Install haystack-ai with pip and follow the quickstart in the docs. - v3.4.1 (2026-10-21): the newest release listed on the official page or repository when we read it on 2026-10-25. ## How to set it up: Get started with Haystack These steps come from the vendor's own pages as read on 2026-10-25. We ran Haystack on 2026-10-25; the test log lists what was and was not covered. 1. **Get access.** Install haystack-ai with pip and follow the quickstart in the docs. 2. **Check the limits and costs first.** Free to self-host. Open-source library; costs come from the model APIs you call. ## Pros and cons Pros: - Apache-2.0 - Active releases Cons: - Python only - Our test was one small task on a local 3B model; it does not show behaviour with hosted models or larger jobs ## Alternatives - [LlamaIndex](https://theagenticweekly.com/tools/llamaindex): Open-source data framework for retrieval-augmented generation and document-centred agents, with a hosted document platform alongside. - [LangChain](https://theagenticweekly.com/tools/langchain): Open-source framework for building LLM applications and agents in Python and JavaScript, from the team behind LangGraph and LangSmith. - [Dify](https://theagenticweekly.com/tools/dify): Open-source platform for building LLM apps and agent workflows with a visual canvas; licensed under a modified Apache 2.0 with extra conditions. - [Langflow](https://theagenticweekly.com/tools/langflow): MIT-licensed visual builder for AI agents and MCP servers with a very large GitHub following. - [Botpress](https://theagenticweekly.com/tools/botpress): Customer-support AI agent platform with a free plan and conversation-based paid plans. - [Gumloop](https://theagenticweekly.com/tools/gumloop): Agent builder for teams; plans start at $37 per month with 20k included credits. - [Lindy](https://theagenticweekly.com/tools/lindy): AI 'employee' builder that connects to your tools; Free plan with $50 in credits that last 7 days, then credit-based plans. - [Microsoft Copilot Studio](https://theagenticweekly.com/tools/copilot-studio): Microsoft's platform for creating and managing custom agents, workflows and apps with no code. - [Pydantic AI](https://theagenticweekly.com/tools/pydantic-ai): Python agent framework built on Pydantic types, covering agents, realtime voice, image generation and embeddings. - [Relevance AI](https://theagenticweekly.com/tools/relevance-ai): Platform for specialist AI agents for sales, customer success, marketing and HR, with an embedded deployment team. - [Voiceflow](https://theagenticweekly.com/tools/voiceflow): Platform for chat and voice AI agents for customer experience teams. - [LangGraph](https://theagenticweekly.com/tools/langgraph): Low-level framework for building long-running, stateful agents as graphs. ## FAQ ### What is Haystack? Haystack's repository is Apache-2.0 licensed with v3.4.1 tagged Oct 21, 2026 and a push on Oct 24, 2026. ### Is Haystack free? Free to self-host. Open-source library; costs come from the model APIs you call. Checked 2026-10-25; prices change, so confirm on the vendor's page. ### What license is Haystack under? Its license: Apache-2.0 (per GitHub). Read from the project's own pages on 2026-10-25. ## What we have not verified - Hosted platform pricing ## Sources - [Haystack](https://haystack.deepset.ai/) (fetched 2026-10-25) - [Haystack repository (GitHub)](https://github.com/deepset-ai/haystack) (fetched 2026-10-25) ## How to cite Agentic Weekly, "Haystack v3.4.1: what's new, verdict & setup", last updated 2026-10-25, https://theagenticweekly.com/tools/haystack Keep the Reported or Tested label when you quote the verdict.