structure [
  | no  marking             key         metre  form                   approx-minutes
  |  1  "Allegro con brio"  :c-minor    "2/4"  "sonata"                            7
  |  2  "Andante con moto"  :a-flat     "3/8"  "double variations"                10
  |  3  "Allegro"           :c-minor    "3/4"  "scherzo and trio"                  5
  |  4  "Allegro"           :c-major    "4/4"  "sonata"                           11
]

a1 69 73 74 72 75 63 74 75 72 65 84 a6 62 6e 6f 01 63 6b 65 79 da 00 01 11 d4 67 63 2d 6d 69 6e 6f 72 64 66 6f 72 6d 66 73 6f 6e 61 74 61 65 6d 65 74 72 65 63 32 2f 34 67 6d 61 72 6b 69 6e 67 70 41 6c 6c 65 67 72 6f 20 63 6f 6e 20 62 72 69 6f 6e 61 70 70 72 6f 78 2d 6d 69 6e 75 74 65 73 07 a6 62 6e 6f 02 63 6b 65 79 da 00 01 11 d4 66 61 2d 66 6c 61 74 64 66 6f 72 6d 71 64 6f 75 62 6c 65 20 76 61 72 69 61 74 69 6f 6e 73 65 6d 65 74 72 65 63 33 2f 38 67 6d 61 72 6b 69 6e 67 70 41 6e 64 61 6e 74 65 20 63 6f 6e 20 6d 6f 74 6f 6e 61 70 70 72 6f 78 2d 6d 69 6e 75 74 65 73 0a a6 62 6e 6f 03 63 6b 65 79 da 00 01 11 d4 67 63 2d 6d 69 6e 6f 72 64 66 6f 72 6d 70 73 63 68 65 72 7a 6f 20 61 6e 64 20 74 72 69 6f 65 6d 65 74 72 65 63 33 2f 34 67 6d 61 72 6b 69 6e 67 67 41 6c 6c 65 67 72 6f 6e 61 70 70 72 6f 78 2d 6d 69 6e 75 74 65 73 05 a6 62 6e 6f 04 63 6b 65 79 da 00 01 11 d4 67 63 2d 6d 61 6a 6f 72 64 66 6f 72 6d 66 73 6f 6e 61 74 61 65 6d 65 74 72 65 63 34 2f 34 67 6d 61 72 6b 69 6e 67 67 41 6c 6c 65 67 72 6f 6e 61 70 70 72 6f 78 2d 6d 69 6e 75 74 65 73 0b

unimsg.net — the specification, presented

The site has one job: to make a reader understand, in about ninety seconds, that a document can be a thing you read and a thing a machine encodes byte-identically, and that the difference is not cosmetic. Everything else on the site is elaboration. If the banner and the first screen fail, no amount of comparison table recovers it.

Every fragment on this site is a real document you can open, and the bytes shown beside it are the bytes the encoder produces for it.

One document, both ways

This is a whole document, not an excerpt — every byte of it. A person reads the left. A machine reads the right. They are the same object, and the encoder produced the right from the left while this page was being built.

%unimsg 0 txn/v1

uses { acme/route-hint #sha256:9f2a3c7d }

transaction @ord-88213 {
  customer external -> @cust-4471
  amount usd 149.99
  receipt ~hex:89504e470d0a1a0a
  digest #sha256:deadbeefcafe
  routing !acme/route-hint { zone 4, prio :high }
  tags [ :urgent, :gift, @promo-x ]
}

[examples/sigils.umsg](examples/sigils.umsg) — an order carrying a decimal amount, a reference, raw bytes, a hash, an extension nothing here understands, and a mixed sequence.

a2 64 75 73 65 73 a1 6f 61 63 6d 65 2f 72 6f 75 74 65 2d 68 69 6e 74 da
00 01 11 d8 82 66 73 68 61 32 35 36 44 9f 2a 3c 7d 6b 74 72 61 6e 73 61
63 74 69 6f 6e da 00 01 11 d5 82 81 da 00 01 11 d6 69 6f 72 64 2d 38 38
32 31 33 a6 64 74 61 67 73 83 da 00 01 11 d4 66 75 72 67 65 6e 74 da 00
01 11 d4 64 67 69 66 74 da 00 01 11 d6 67 70 72 6f 6d 6f 2d 78 66 61 6d
6f 75 6e 74 da 00 01 11 d5 82 81 da 00 01 11 d4 63 75 73 64 c4 82 21 19
3a 97 66 64 69 67 65 73 74 da 00 01 11 d8 82 66 73 68 61 32 35 36 46 de
ad be ef ca fe 67 72 65 63 65 69 70 74 48 89 50 4e 47 0d 0a 1a 0a 67 72
6f 75 74 69 6e 67 da 00 01 11 d9 82 6f 61 63 6d 65 2f 72 6f 75 74 65 2d
68 69 6e 74 a2 64 70 72 69 6f da 00 01 11 d4 64 68 69 67 68 64 7a 6f 6e
65 04 68 63 75 73 74 6f 6d 65 72 da 00 01 11 d5 82 81 da 00 01 11 d4 68
65 78 74 65 72 6e 61 6c da 00 01 11 d7 69 63 75 73 74 2d 34 34 37 31

canonical CBOR, deterministically encoded 287 bytes

Open it in the document viewer — every sigil above explained, by pointing at it.

The extension !acme/route-hint is one this site knows nothing about. It survives the round trip intact, and it is legible on the way past — which is the rule that distinguishes an extension from a private convention.

Where to go

An agent reading this site should not have to parse marketing prose to find the grammar. /spec/unimsg-v0.umsg and /corpus/cases.umsg are served as-is at stable paths, linked from every page, and are the same bytes the project publishes. The site is a rendering of them, never a paraphrase that could drift.