Side by side
Haystack vs Vellum
Both stand on llm application development frameworks. Which one you can start free with, which one lets you read the code, and what each costs once you pay.
Free plan APISelf-hosted
Haystack provides a free framework for assembling AI systems from modular pipelines, with integrations and self-hosted deployment options.
Visit Haystack Free plan Open source AndroidAPIExtension+5
Vellum offers a personal assistant with saved context, skills, integrations and approval controls. Consider its internet requirement and default AI data routing, and note the available Linux access options if you use Linux.
Visit VellumThe facts
| Haystack | Vellum | |
|---|---|---|
| Free plan | Yes | Yes |
| Open source | Not published | Yes |
| Runs on | API, Self-hosted | Android, API, Extension, iPhone, Mac, Self-hosted, Web, Windows |
| Lowest paid plan | Free or on request | Mighty: $30 a month |
| Plans published | 2 | 6 |
| Maker | Not published | Not published |
| Website | haystack.deepset.ai | vellum.ai |
| On llm application development frameworks | #6 of 49 | #2 of 49 |
Haystack: what it does well
- Free, open-source Python framework.
- 189 listed integrations across several tool categories.
- Pipelines can be served as REST APIs or MCP servers.
- Supports hybrid search, reranking and RAG workflow building.
What to know first
- Enterprise trial requires a form request.
Vellum: what it does well
- Saves preferences and context across conversations.
- Users can create and manage custom skills.
- Sensitive actions can require approval.
- Cloud assistants run in isolated environments with private storage.
- Optional analytics and crash diagnostics are off by default.
What to know first
- Requires an internet connection to reach an AI provider.
- No shipped Linux desktop client.
- Conversation context goes to Anthropic by default.
- Paid plans start at $30/month.
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