yarn install
yarn build
main.mts:1:28 - error TS7016: Could not find a declaration file for module 'rxjs'. '/data/projects/various/rxjs-ts-node12/node_modules/rxjs/dist/cjs/index.js' implicitly has an 'any' type.
Try `npm i --save-dev @types/rxjs` if it exists or add a new declaration (.d.ts) file containing `declare module 'rxjs';`
1 import { Observable } from "rxjs";
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Found 1 error.