# TypeScript build errors after upgrading optimizely-sdk to 4.1.1

optimizely-sdk 4.1.1 accidentally shipped raw TypeScript sources, which breaks consumer builds with TS errors that tsconfig exclude and skipLibCheck cannot fix. Upgrade to 4.4.3 (react-sdk 2.4.1), which ships only the compiled dist output again. If you are pinned, 4.3.4 also builds fine as a stopgap.

## Context from the issue
gh:optimizely/javascript-sdk#613: Issue optimizely/javascript-sdk#613 (closed, 10 comments): version 4.1.1 shipped raw TypeScript sources instead of just the compiled dist output, so consuming apps (including via react-sdk) failed to build with TS errors that tsconfig exclude and skipLibCheck could not fix. Maintainers fixed the packaging and released optimizely-sdk 4.4.3, with react-sdk 2.4.1.