Adding eslint rules using eslint-plugin-jsx-a11y to Sprout Social's web app repository as warnings and flipping them to errors once they are resolved.
Added helper functions using jest-axe so we can include accessibility in our unit tests.
Teaching my fellow web coworkers more about accessibility and making sure our design system is built with accessibility baked in from the beginning.
Learning react-testing-library - I really like how accessibility is built in, such as that you can query by label id and test the application as a user would use it.