Handle Unix time in Swift for iOS/macOS development.
// Current timestamp (TimeInterval is double)
let now = Date().timeIntervalSince1970// Date to timestamp
let date = ISO8601DateFormatter().date(from: "2024-01-01T00:00:00Z")!
let ts = date.timeIntervalSince1970// Timestamp to date
let date = Date(timeIntervalSince1970: 1704067200)