.u
2 claimants
2 primary
0 secondary
shared primary (2)
SWH popularity
Distinct files in the full Software Heritage archive (2026-06-04 export), dated by first appearance, following Desmazières, Di Cosmo, Lorentz (MSR 2025). Case-aggregated. citation.
93.2K
total files
28.6K
first seen 2021–2025 (30.7%)
2020
median year (half its files since)
Case variants in archive: .u (66.6K), .U (26.6K) — aggregated above.
Attribution status
This extension is attributed to ucode; Urbiscript as primary by 2 authoritative claims.
Authoritative sources: ✗ Linguist · no claim ✓ Pygments ✗ Wikidata · no claim △ Wikipedia · secondary
Claimants (3)
Languages that list
.u among their extensions. Strength reflects whether the upstream source treated it as their primary extension.| Language | Source | Strength |
|---|---|---|
| ucode | pygments | primary |
| Urbiscript | pygments | primary |
| Urbiscript | wikipedia | proposed |
Wikidata says… (3)
File formats, image formats, audio codecs and other non-PL
entities that claim
.u on Wikidata
(property P1195) or in the Wikipedia infobox.
Source: data/derived/external_extension_index.csv.
Click Use as new PL on any row to open the
Add-PL form pre-filled with that entry's name, Wikipedia/Wikidata
URL, and this extension — one submission creates the PL + claim.
| Format | Class (Wikidata P31) | Suggested label | MIME | Notes | Action |
|---|---|---|---|---|---|
| KICK-Pascal Unit Interface Q105856675 file format | file format | — | application/octet-stream | — | Use as new PL ↗ |
| Twist Update script Q105856725 file format | file format | — | text/plain | — | Use as new PL ↗ |
| UrbiScript source code file Q131341835 file format | file format | — | application/x-urbiscript | — | Use as new PL ↗ |
SWH-mined examples (0)
No archived examples for .u in our local mirror yet.