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Upgrade paths

This page shows the migration guides to the latest versions of the Langfuse SDKs. Pick your SDK to follow the relevant migration steps.

Python SDK

Python SDK v3 → v4 — Latest
Python SDK v2 → v3

JS/TS SDK

JS/TS SDK v4 → v5 — Latest
JS/TS SDK v3 → v4

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Troubleshooting & FAQ

Resolve common Python and JS/TS SDK issues with side-by-side guidance.

Python v3 → v4

Migration guide for upgrading the Langfuse Python SDK from v3 to v4.

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Upgrade paths Python SDK JS/TS SDK

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