Compare frameworks
Guardrails vs Letta vs CrewAI
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 | Guardrails | Letta | CrewAI |
|---|---|---|---|
| Stars | 7,443Synced from sourceCurrent4h ago | 24,864Synced from sourceCurrent4h ago | 58,958 (highest of the compared values)Synced from sourceCurrent4h ago |
| Last commit | 2026-09-22Synced from sourceCurrent4h ago | 2026-09-10Synced from sourceCurrent4h ago | 2026-09-23Synced from sourceCurrent4h ago |
| Language | pythonSeeded, unreviewedwritten 1mo ago | pythonSeeded, unreviewedwritten 1mo ago | pythonSeeded, unreviewedwritten 1mo ago |
| Licence | Apache-2.0Synced from sourceCurrent4h ago | Apache-2.0Synced from sourceCurrent4h ago | MITSynced from sourceCurrent4h ago |
| Archived | noSynced from sourceCurrent4h ago | noSynced from sourceCurrent4h ago | noSynced from sourceCurrent4h ago |
| Category | validationSeeded, unreviewedwritten 1mo ago | memorySeeded, unreviewedwritten 1mo ago | multi-agentSeeded, unreviewedwritten 1mo ago |
| Contributors | 79Synced from sourceCurrent4h ago | 155Synced from sourceCurrent4h ago | 340Synced from sourceCurrent4h ago |
| Forks | 708Synced from sourceCurrent4h ago | 2628Synced from sourceCurrent4h ago | 8560Synced from sourceCurrent4h ago |
| Maintainer | Guardrails AISeeded, unreviewedwritten 1mo ago | LettaSeeded, unreviewedwritten 1mo ago | CrewAISeeded, unreviewedwritten 1mo ago |
| Open issues | 80Synced from sourceCurrent4h ago | 0Synced from sourceCurrent4h ago | 463Synced from sourceCurrent4h ago |
| PyPI package | guardrails-aiSynced from sourceCurrent4h ago | lettaSynced from sourceCurrent4h ago | crewaiSynced from sourceCurrent4h ago |
| PyPI released | 2026-08-14T14:22:27.750056ZSynced from sourceCurrent4h ago | 2026-09-23T23:59:05.225455ZSynced from sourceCurrent4h ago | 2026-09-16T22:10:41.471882ZSynced from sourceCurrent4h ago |
| Requires Python | <3.14,>=3.10Synced from sourceCurrent4h ago | >=3.9Synced from sourceCurrent4h ago | <3.14,>=3.10Synced from sourceCurrent4h ago |
| PyPI version | 0.11.0Synced from sourceCurrent4h ago | 0.33.0Synced from sourceCurrent4h ago | 1.15.22Synced from sourceCurrent4h ago |
| Repository | https://github.com/guardrails-ai/guardrailsSynced from sourceCurrent4h ago | https://github.com/letta-ai/lettaSynced from sourceCurrent4h ago | https://github.com/crewAIInc/crewAISynced 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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