# td36 Time-delta identifiers: a timestamp is stored as the base36 encoding of its offset from a chosen epoch, so ids stay short, sortable and monotonically increasing. ```rust use td36::{Td36Epoch, Td36Precision}; let epoch = Td36Epoch::new(1_700_000_000, Td36Precision::Seconds); let id = epoch.encode(1_700_000_123).unwrap(); assert_eq!(epoch.decode_id(&id).unwrap(), 1_700_000_123); ``` `Td36Epoch::encode_epoch_marker` / `decode_epoch_marker` round-trip the epoch itself, so a stream of ids can carry the epoch it is relative to. No dependencies. `cargo test` covers epoch round-tripping and the before-epoch guard.