Retry with Fibonacci backoff

Program.cs

var retry = 1;
var nextRetry = 1;
while (true)
{
    try
    {
        DoSomething();
        break;
    }
    catch (TransientException) when (retry <= 8)
    {
        Thread.Sleep(TimeSpan.FromMinutes(retry));
        (retry, nextRetry) = (nextRetry, retry + nextRetry);
    }
}