Compare frameworks
LangChain vs Haystack vs Pydantic AI
Every figure below carries the source that reported it and the moment it was observed. Values that failed validation are withheld rather than shown, and a dash means no source we track carries that field for that framework.
| Field | LangChain | Haystack | Pydantic AI |
|---|---|---|---|
| Stars | 146,956 (highest of the compared values)Synced from sourceCurrent3h ago | 26,584Synced from sourceCurrent3h ago | 20,133Synced from sourceCurrent3h ago |
| downloads | 2,026,447Synced from sourceCurrent3h ago | — | 3,076,771 (highest of the compared values)Synced from sourceStale1mo ago· past SLA |
| Last commit | 2026-09-24Synced from sourceCurrent3h ago | 2026-09-23Synced from sourceCurrent3h ago | 2026-09-24Synced from sourceCurrent3h ago |
| Language | pythonSeeded, unreviewedwritten 1mo ago | pythonSeeded, unreviewedwritten 1mo ago | pythonSeeded, unreviewedwritten 1mo ago |
| Licence | MITSynced from sourceCurrent3h ago | Apache-2.0Synced from sourceCurrent3h ago | MITSynced from sourceCurrent3h ago |
| Archived | noSynced from sourceCurrent3h ago | noSynced from sourceCurrent3h ago | noSynced from sourceCurrent3h ago |
| Category | orchestrationSeeded, unreviewedwritten 1mo ago | ragSeeded, unreviewedwritten 1mo ago | structured-outputSeeded, unreviewedwritten 1mo ago |
| Contributors | 3740Synced from sourceCurrent3h ago | 475Synced from sourceCurrent3h ago | 589Synced from sourceCurrent3h ago |
| Forks | 24587Synced from sourceCurrent3h ago | 3176Synced from sourceCurrent3h ago | 2768Synced from sourceCurrent3h ago |
| Maintainer | LangChainSeeded, unreviewedwritten 1mo ago | deepsetSeeded, unreviewedwritten 1mo ago | PydanticSeeded, unreviewedwritten 1mo ago |
| npm downloads, monthly | 10553700Synced from sourceCurrent3h ago | — | — |
| npm downloads, weekly | 2026447Synced from sourceCurrent3h ago | — | — |
| npm package | langchainSynced from sourceCurrent3h ago | — | — |
| npm window ends | 2026-09-21Synced from sourceCurrent3h ago | — | — |
| Open issues | 561Synced from sourceCurrent3h ago | 168Synced from sourceCurrent3h ago | 965Synced from sourceCurrent3h ago |
| PyPI downloads, monthly | — | — | 13478631Synced from sourceStale1mo ago· past SLA |
| PyPI downloads, weekly | — | — | 3076771Synced from sourceStale1mo ago· past SLA |
| PyPI package | langchainSynced from sourceCurrent3h ago | haystack-aiSynced from sourceCurrent3h ago | pydantic-aiSynced from sourceCurrent3h ago |
| PyPI released | 2026-09-18T17:31:10.056247ZSynced from sourceCurrent3h ago | 2026-09-03T09:27:43.312258ZSynced from sourceCurrent3h ago | 2026-09-24T03:23:01.147978ZSynced from sourceCurrent3h ago |
| Requires Python | <4.0.0,>=3.10.0Synced from sourceCurrent3h ago | >=3.10Synced from sourceCurrent3h ago | >=3.10Synced from sourceCurrent3h ago |
| PyPI version | 1.4.2Synced from sourceCurrent3h ago | 3.1.1Synced from sourceCurrent3h ago | 2.49.0Synced from sourceCurrent3h ago |
| Repository | https://github.com/langchain-ai/langchainSynced from sourceCurrent3h ago | https://github.com/deepset-ai/haystackSynced from sourceCurrent3h ago | https://github.com/pydantic/pydantic-aiSynced from sourceCurrent3h ago |
Sources: GitHub REST API, npm registry downloads, PyPI registry metadata, pypistats.org downloads. Most recent observation 3h ago. Where a row is marked, ▲ is the highest of the values shown and ▼ the lowest — arithmetic on the figures above, not a ranking or a recommendation. Rows where neither extreme is meaningful are left unmarked rather than given a direction they do not have.
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