iso_timestamp

Cross-target ISO 8601 timestamp helpers.

Gleam’s stdlib doesn’t include date/time formatting, so we delegate to platform natives via FFI: Erlang’s calendar:system_time_to_rfc3339 and JavaScript’s Date.prototype.toISOString. Both produce the canonical form YYYY-MM-DDTHH:MM:SS.sssZ that Shopify Admin timestamps use.

Inputs and outputs are millisecond Unix epochs to keep arithmetic in the synthetic identity registry trivial.

Values

format_iso

pub fn format_iso(ms: Int) -> String

Format ms (milliseconds since the Unix epoch) as YYYY-MM-DDTHH:MM:SS.sssZ.

now_iso

pub fn now_iso() -> String

Wall-clock current time, formatted as YYYY-MM-DDTHH:MM:SS.sssZ. Used by dump_state for the createdAt field of the envelope. This is non-deterministic; callers that want a fixed timestamp should pass one explicitly to dump_state.

parse_iso

pub fn parse_iso(iso: String) -> Result(Int, Nil)

Parse an ISO 8601 timestamp string back to milliseconds since epoch. Returns Error(Nil) if the input is not a valid timestamp the underlying platform can parse.