# Date Versioning (DateVer)

> A versioning standard in which a version number is the date it was released: YY.MM.DD, with -1, -2 and so on for further releases on the same day. Created and maintained by Stux.Group. Current specification: 26.10.01-2.

The essentials (the specification is the source of truth):

- Format: YY.MM.DD, each part two digits and zero-padded, a real Gregorian calendar date. Example: 26.10.01.
- From the year 2100 the year is written in full, with no leading zeros: 2100.01.01, and 10000.01.01 in the year 10000. Never write 2000-2099 in full (26.10.01, not 2026.10.01). There is no end date.
- The date is the UTC date of the release.
- Further releases on the same UTC date append -N, counting from 1 with no gaps: 26.10.01-1, 26.10.01-2. Never -0.
- Precedence: compare the year (YY means 20YY), MM, DD, then N, all numerically (no suffix means N = 0), so 26.10.01 < 26.10.01-1 < 26.10.02 and 99.12.31 < 2100.01.01. Later versions always rank higher.
- Never compare a Date Version with SemVer rules: in SemVer 26.10.1-1 ranks before 26.10.1, but in DateVer 26.10.01-1 ranks after 26.10.01.
- SemVer form, for registries that only accept SemVer: MAJOR = the year minus 2000 (YY without leading zeros; 2100 gives 100), MINOR = MM without leading zeros, PATCH = DD x 100 + N. Example: 26.10.01-2 becomes 26.10.102, 05.03.09-4 becomes 5.3.904. A project whose old SemVer versions would outrank that form (major already 26 or more) adds a fixed major offset, the smallest multiple of 100 that fixes it: 26.10.01 becomes 126.10.100.
- Switching from another scheme: say so in the first Date Version's changelog entry; every Date Version ranks above every version from before the switch.
- Optional build metadata after a plus sign (+build.7) is ignored for precedence. A leading v is only for tag names (v26.10.01).

## Specification

- [Date Versioning specification (Markdown, latest)](https://datevers.ing/spec/latest.md): the full, current specification as plain text (also at https://datevers.ing/spec.md)
- [Date Versioning specification (web page, latest)](https://datevers.ing/spec/latest/): always the current specification, rendered
- Every specification URL also works with .txt (plain text), .json and .xml (structured: metadata, the numbered rules and every section) and .html: for example https://datevers.ing/spec/latest.txt, https://datevers.ing/spec/latest.json, https://datevers.ing/spec/26.10.01-2.xml
- [Date Versioning 26.10.01-2 (Markdown, permanent)](https://datevers.ing/spec/26.10.01-2.md): this version of the specification, permanently
- [Date Versioning 26.10.01-2 (web page)](https://datevers.ing/spec/26.10.01-2/): the same, rendered

## Optional

- [Machine-readable descriptor](https://datevers.ing/datever.json): regular expressions, time zone and SemVer-form rules as JSON
- [Website](https://datevers.ing/): the specification with a version validator and a next-version tool
- [Source and issue tracker](https://github.com/StuxGroup/DateVersioning)