Taught TypeScript
used TypeScript
Our org is adopting Typescript and I contributed to the migration effort by merging changes to support Typescript in one of our major repos. 

Typescript support required configuration changes to our testing framework, bundler, CI, and linters. Since most of our team is new to Typescript, I also held a meeting to walk through a PR that converted a bunch of Javascript files and gave a basic rundown of Typescript development.