The archive that outlives its software
A .at1century file carries, in one blob: an English description of its own format, the decoder as source in a tiny procedural language, a SHA-256 of the original, and the compressed payload. It reconstructs byte-exact using only what it carries — the embedded decoder run in a bare namespace, no imports, nothing from AT-1 — so it is still decodable when no AT-1 software, or even Python, survives. Any implementer can rewrite the decoder from the paragraph alone.
- 1,494 B
- total self-description: English spec + decoder source
- no software
- reconstructs from the embedded decoder alone, bare namespace
- byte-exact
- native and embedded decoders agree; SHA-256 verified
- 2126-ready
- rewritable by any implementer from the English paragraph
Pack it, and it explains itself
at1 century pack records.csv -o records.at1century # 1,142,180 -> 316,069 bytes (3.61x); self-description # overhead 1,494 bytes at1 century spec records.at1century # read the rebuild instructions at1 century verify records.at1century # native == embedded, SHA-256 ok at1 century unpack records.at1century -o out.csv --self-decode # recovered via the embedded decoder alone
Self-describing
The English spec is inside the file. The decoder is source, not a binary — auditable, portable, and rewritable by hand from the spec.
Two decoders, one answer
A fast native decoder for daily use and the embedded decoder for the guarantee — both must produce byte-identical output, checked against the SHA-256.
Honest scope
The embedded decoder runs in a bare namespace (four safe builtins, no imports). It’s an integrity + longevity guarantee, not confidentiality; open only archives you trust.
Billed per GB packed — first 10 GB/month free. See pricing.