> For the complete documentation index, see [llms.txt](https://docs.tryterra.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tryterra.co/faq/help-topics/data-api-sdk/api-endpoints-errors-and-migrations/js-sdk-deprecation-backend-sdk-versions.md).

# Is the JavaScript SDK deprecated?

**The legacy JavaScript npm package still functions but no longer receives updates and was removed from the docs.**

* Existing integrations keep running, but **build new functionality against the REST API directly**.
* For the **backend SDK**, there's no official migration guide between major versions yet. The new major release changes most function signatures (breaking), while data models stay largely similar, and it is completely safe to stay on the previous 1.x version if it works for you.
* **Mobile packages** (for example, React Native) are versioned separately and serve a different purpose: connecting mobile integrations.

See the [SDK references](https://docs.tryterra.co/reference/health-and-fitness-api/sdk-references) for current packages.