// Instant represents time from epoch
Instant now = SystemClock.Instance.Now;

// Convert an instant to a ZonedDateTime
ZonedDateTime nowInIsoUtc = now.InUtc();

// Create a duration
Duration duration = Duration.FromMinutes(3);

// Add it to our ZonedDateTime
ZonedDateTime thenInIsoUtc = nowInIsoUtc + duration;

// Timezone support (multiple providers)
var london = DateTimeZoneProviders.Tzdb["Europe/London"];

// Timezone conversions
var localDate = new LocalDateTime(2012, 3, 27, 0, 45, 00);
var before = london.AtStrictly(localDate);