In [[TypeScript]] there are two syntaxes (are there more?) for defining a type of an object, either [[Index signature]] or the [[Record utility]]. In my opinion, the Record syntax is more readable.

type Server = 'dev' | 'stage' | 'production'
	  
// Index signature
const serversIndex: { [key in Server]: string } = {
  dev: 'url-dev',
  stage: 'url-stage',
  production: 'url-production'
} as const
	  
// Using the Record utility
const serversRecord: Record<Server, string> = {
  dev: 'url-dev',
  stage: 'url-stage',
  production: 'url-production'
} as const