Compare frameworks
Instructor vs Pydantic AI vs Haystack
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 | Instructor | Pydantic AI | Haystack |
|---|---|---|---|
| Stars | 13,939Synced from sourceCurrent4h ago | 20,133Synced from sourceCurrent4h ago | 26,584 (highest of the compared values)Synced from sourceCurrent4h ago |
| downloads | 13,080,962 (highest of the compared values)Synced from sourceStale1mo ago· past SLA | 3,076,771Synced from sourceStale1mo ago· past SLA | — |
| Last commit | 2026-09-22Synced from sourceCurrent4h ago | 2026-09-24Synced from sourceCurrent4h ago | 2026-09-23Synced from sourceCurrent4h ago |
| Language | pythonSeeded, unreviewedwritten 1mo ago | pythonSeeded, unreviewedwritten 1mo ago | pythonSeeded, unreviewedwritten 1mo ago |
| Licence | MITSynced from sourceCurrent4h ago | MITSynced from sourceCurrent4h ago | Apache-2.0Synced from sourceCurrent4h ago |
| Archived | noSynced from sourceCurrent4h ago | noSynced from sourceCurrent4h ago | noSynced from sourceCurrent4h ago |
| Category | structured-outputSeeded, unreviewedwritten 1mo ago | structured-outputSeeded, unreviewedwritten 1mo ago | ragSeeded, unreviewedwritten 1mo ago |
| Contributors | 267Synced from sourceCurrent4h ago | 589Synced from sourceCurrent4h ago | 475Synced from sourceCurrent4h ago |
| Forks | 1262Synced from sourceCurrent4h ago | 2768Synced from sourceCurrent4h ago | 3176Synced from sourceCurrent4h ago |
| Maintainer | 567 LabsSeeded, unreviewedwritten 1mo ago | PydanticSeeded, unreviewedwritten 1mo ago | deepsetSeeded, unreviewedwritten 1mo ago |
| Open issues | 90Synced from sourceCurrent4h ago | 965Synced from sourceCurrent4h ago | 168Synced from sourceCurrent4h ago |
| PyPI downloads, monthly | 27671654Synced from sourceStale1mo ago· past SLA | 13478631Synced from sourceStale1mo ago· past SLA | — |
| PyPI downloads, weekly | 13080962Synced from sourceStale1mo ago· past SLA | 3076771Synced from sourceStale1mo ago· past SLA | — |
| PyPI package | instructorSynced from sourceCurrent4h ago | pydantic-aiSynced from sourceCurrent4h ago | haystack-aiSynced from sourceCurrent4h ago |
| PyPI released | 2026-09-09T02:25:54.888746ZSynced from sourceCurrent4h ago | 2026-09-24T03:23:01.147978ZSynced from sourceCurrent4h ago | 2026-09-03T09:27:43.312258ZSynced from sourceCurrent4h ago |
| Requires Python | <4.0,>=3.9Synced from sourceCurrent4h ago | >=3.10Synced from sourceCurrent4h ago | >=3.10Synced from sourceCurrent4h ago |
| PyPI version | 1.17.0Synced from sourceCurrent4h ago | 2.49.0Synced from sourceCurrent4h ago | 3.1.1Synced from sourceCurrent4h ago |
| Repository | https://github.com/567-labs/instructorSynced from sourceCurrent4h ago | https://github.com/pydantic/pydantic-aiSynced from sourceCurrent4h ago | https://github.com/deepset-ai/haystackSynced from sourceCurrent4h ago |
Sources: GitHub REST API, npm registry downloads, PyPI registry metadata, pypistats.org downloads. Most recent observation 4h 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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