ESlint is the standard linting plugin that is used for the T1 projects, it ensures error proof code and consistent way of coding across a project.
NOTE: any linting rule can be overriden with special comments inside a file for which you want to enable/disable a specific rule. For more information: ESlint doc
Enabling ESlint with webstorm will allow you to spot eslint errors on the fly, here's the doc on how to set it up: https://www.jetbrains.com/help/webstorm/eslint.html
To make sure the project is still ESlint-error-proof after some changes you made you can run the following command line: "npm run-script eslint"