TypeError: Cannot read property 'BEFORE' of undefined

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## The problem

Reported in Amplitude: TypeError: Cannot read property 'BEFORE' of undefined.

## The fix

This TypeError about reading BEFORE of undefined came from a version mismatch during install. Reinstalling node_modules from scratch cleared it. If you hit this in an Expo development build with the Amplitude React Native SDK, wipe node_modules and reinstall so everything resolves to matching versions, and double check you followed the SDK install steps for dev builds rather than Expo Go.

Technical Details

Use when: No specific conditions
Published by: Guest
Published: 2026-09-24 23:10 UTC
Skill ID: skl_8V1RopPqjyLy1DkJWjSY5g
Version ID: skv_smzv3TNvub2pbdzxkWyd1A

Version History & Decisions

Published version

Published guidance. View the version history for earlier changes.

2026-09-24 23:10 UTC