All of TOML

toml.parse reads TOML 1.0 in full, and toml.encode writes it. Arrays, floats, inline tables, dotted keys, arrays of tables and the four date and time types all parse, so a config file written to the spec is a config file SCUA can read.

import toml

match toml.parse(text)
  Ok(cfg) -> print((cfg @ "worker")[1] @ "name")
  Error(why) -> print(why)
end

An array is an array you can index and iterate. [[worker]] is an array of tables, in file order. A date is a datetime you can do arithmetic on rather than a string you have to parse again. Integers take the 0x, 0o and 0b bases and 1_000 underscores, floats take inf and nan, and strings come in all four TOML spellings with escapes processed where the spec says they should be.

The parser is a rewrite rather than an extension. Arrays and inline tables span lines, so a line-at-a-time shape could not reach them at any amount of effort. If you carry a workaround for a TOML construct SCUA did not read, you can drop it.

Dates are checked rather than normalised. 1979-99-99 and 2026-01-32 are refused as the impossible dates they are, with leap years counted properly, so a typo in a config file stops the run instead of becoming a plausible neighbouring date. A document that fails to parse names the line it failed on.

toml.encode sorts its keys, so the same table produces the same text every run and a config file does not reshuffle itself in version control. Exact decimal and money values are written as strings, because TOML's only number types are 64-bit integer and float and either would drop the exactness those types exist to hold. A value with no TOML form at all, like bytes, raises a fault instead of being approximated into one.

Before you round-trip a file, two limits. A bare local time, 07:32:00 with no date, reads as a string, because SCUA has no time-of-day type and inventing a date for it would be worse than saying so. And a date's spelling does not survive a read-modify-write: a datetime is an instant plus an offset and carries no record of having been written date-only, so 2026-08-19 read in and written back out comes out as 2026-08-19T00:00:00Z. Same instant, longer spelling. Where the exact shape of a file matters, edit the text.