Environment specific appsettings to override values from appsettings.json.

appsettings.json5

// appsettings.Development.json
{
  "Mode": "Development"
}

// appsettings.Test.json
{
  "Mode": "Test"
}

// appsettings.Staging.json
{
  "Mode": "Staging"
}

// appsettings.Production.json
{
  "Mode": "Production"
}

// If object is nested deep, then this approach would need you to 
// recreate the nesting in the environment specific file.
// as shown below for just overriding Default LogLevel setting.
// {
//   "Logging": {
//     "LogLevel": {
//       "Default": "Information"
//     }
// }
}