Compare frameworks
Haystack vs LlamaIndex vs Letta
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 | Haystack | LlamaIndex | Letta |
|---|---|---|---|
| Stars | 26,584Synced from sourceCurrent3h ago | 52,306 (highest of the compared values)Synced from sourceCurrent3h ago | 24,864Synced from sourceCurrent3h ago |
| downloads | — | 83,631Synced from sourceCurrent3h ago | — |
| Last commit | 2026-09-23Synced from sourceCurrent3h ago | 2026-09-24Synced from sourceCurrent3h ago | 2026-09-10Synced from sourceCurrent3h ago |
| Language | pythonSeeded, unreviewedwritten 1mo ago | pythonSeeded, unreviewedwritten 1mo ago | pythonSeeded, unreviewedwritten 1mo ago |
| Licence | Apache-2.0Synced from sourceCurrent3h ago | MITSynced from sourceCurrent3h ago | Apache-2.0Synced from sourceCurrent3h ago |
| Archived | noSynced from sourceCurrent3h ago | noSynced from sourceCurrent3h ago | noSynced from sourceCurrent3h ago |
| Category | ragSeeded, unreviewedwritten 1mo ago | ragSeeded, unreviewedwritten 1mo ago | memorySeeded, unreviewedwritten 1mo ago |
| Contributors | 475Synced from sourceCurrent3h ago | 1999Synced from sourceCurrent3h ago | 155Synced from sourceCurrent3h ago |
| Forks | 3176Synced from sourceCurrent3h ago | 8203Synced from sourceCurrent3h ago | 2628Synced from sourceCurrent3h ago |
| Maintainer | deepsetSeeded, unreviewedwritten 1mo ago | LlamaIndexSeeded, unreviewedwritten 1mo ago | LettaSeeded, unreviewedwritten 1mo ago |
| npm downloads, monthly | — | 429018Synced from sourceCurrent3h ago | — |
| npm downloads, weekly | — | 83631Synced from sourceCurrent3h ago | — |
| npm package | — | llamaindexSynced from sourceCurrent3h ago | — |
| npm window ends | — | 2026-09-21Synced from sourceCurrent3h ago | — |
| Open issues | 168Synced from sourceCurrent3h ago | 849Synced from sourceCurrent3h ago | 0Synced from sourceCurrent3h ago |
| PyPI package | haystack-aiSynced from sourceCurrent3h ago | llama-indexSynced from sourceCurrent3h ago | lettaSynced from sourceCurrent3h ago |
| PyPI released | 2026-09-03T09:27:43.312258ZSynced from sourceCurrent3h ago | 2026-09-21T16:22:20.056831ZSynced from sourceCurrent3h ago | 2026-09-23T23:59:05.225455ZSynced from sourceCurrent3h ago |
| Requires Python | >=3.10Synced from sourceCurrent3h ago | <4.0,>=3.10Synced from sourceCurrent3h ago | >=3.9Synced from sourceCurrent3h ago |
| PyPI version | 3.1.1Synced from sourceCurrent3h ago | 0.14.25Synced from sourceCurrent3h ago | 0.33.0Synced from sourceCurrent3h ago |
| Repository | https://github.com/deepset-ai/haystackSynced from sourceCurrent3h ago | https://github.com/run-llama/llama_indexSynced from sourceCurrent3h ago | https://github.com/letta-ai/lettaSynced 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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