u

Run it in your browser · Download for offline use

Open the link and use the controls. No Python, terminal, account or installation is required. The download is one HTML file: open it in a browser that permits local HTML and JavaScript. It contains the logic, device protocol, source and license and makes no network requests. A phone that only previews downloaded HTML can use the hosted link instead.

Universal, unknown, unclassified, or another U name. Its wider purpose stays open; each implemented action has a stated scope. Two related layers:

Layer	What runs	Source
Logic	Three string values (1, 0, u), not, and, or, and a guard requiring a reason for u	u.js, u.py, u.sh
Device protocol	Registered adapters, scoped evidence and hash-chained receipts; a fingerprint display with timed hide, rotation and Restore	u.mjs, STANDARD.md

The values can label holds, does not hold, and unknown. The logic combines those labels; it does not perform measurements or authenticate a caller's claim. Two-valued logic does not itself force a program to lie.

The fish keeps swimming

The browser entry carries a value along two cycloid segments, one reflected, with adjustable relative angle, phase and pace. Swimming advances process time; NOT exchanges the branch labels at that same time. A geometric intersection never merges the labels: with asymmetry, the branches may reach it at different times. An unsettled u keeps its reason and both candidate branches. Dotted tails continue past the numerically located intersection; the process can advance beyond the displayed section.

The fractal depth control repeats the whole fish on each of its two branches, forming a tree of smaller fish. Depth 0 shows the original; depth 6 shows 127 copies, each generation at 55% of its parent's scale. Every copy inherits the angle, phase and pace. The marker stays on the original fish. This is a finite preview of a recursive construction; copy addresses do not add truth values. The reusable transforms are exported from u/fish-fractal.

Like Pando, the repeated forms suggest connection and a shared origin. This is an analogy; the fish is not a biological model of Pando or biodiversity.

import {carry, swim, negate, positions, geometry} from 'u/fish';
const later = swim(carry('0'), 1);
later.value;                 // '0': movement does not change truth
negate(later).value;         // '1': NOT exchanges the carried label
const reference = geometry({angle: 0, phase: 0, pace: 1});
positions(carry('u', 1, 'Read the recorded branch label.'), reference);
// In the symmetric reference, two labelled candidates share the crossing.

This is a proposed geometric representation of state transport and negation. It does not make the fish a necessary shape of binary logic or define geometric AND and OR. The three existing values, U2/U5 encodings and behavior tape remain unchanged. Defaults of 3 degrees, phase 0.05 and pace 1.05 are adjustable illustrations, not measured constants. With asymmetry, NOT is generally not a simple reflection of the displayed point. Coordinates and intersection locations are approximate; graphFor exports the curve formulas for an exact calculator. FISH.md records the W/R/A account, correction and checks.

What U has to do with Rod

Rod is intended as a gesture and bone-conduction interface. Rod routes its palp-rod/1 drafts, optional Joy-Con rumble and audio through this U protocol. Its authenticated chat connection remains ChuuWork's. A bone-conduction headset or an audio-connected rod transducer can use the same audio.mjs adapter through the system audio output. Their physical connection, bone conduction and perceived result need observation on that setup.

The U browser entry exercises software, not a connected rod. U is not a site-wide controller for ChuuMind or its subdomains. Rod is one application; its working channels do not define every possible meaning of U.

import {createU} from './u.mjs';
import {createAudioAdapter} from './audio.mjs';
const device = await createU({name:'Any U name'});
device.register('audio', createAudioAdapter());
// Call from a user's button, after choosing the system audio output:
await device.send('audio', {kind:'tone', count:1});
await device.stop(); // Resume explicitly before another send.

The audio adapter starts nothing on construction. It supports bounded tones and explicitly requested speech with a local system voice. No exposed local voice stays U. A completion receipt reports browser execution, never what a person heard. See STANDARD.md for the contract.

U2-bytes: three witnesses in four bits

Justichuu, 3 October 2026: "Rules for U2, only build off u, as i would." A U2-byte holds three witnesses: two bits that say 1 or 0, and one u-bit that may also say u. Its face is 1 only when all three say 1, 0 only when all three say 0, and u until they agree. It packs into four bits; the u-bit's pattern 01 is a bare u and is refused. u2.js builds every face from u.js and holds no table of its own.

import {agree, pack, unpack} from './u2.js';
agree('1', '1', 'u');  // 'u': one witness has not settled
pack('1', '1', '1');   // 15, all three agree on 1
unpack(0b0110);        // ['0', '1', '0']

Optional: use the logic in your own code

import {u, not, and, or} from './u.js';
const x = u('A measurement of the named condition would settle it');
or(x, not(x));  // 'u' under these tables
and(x, not(x)); // 'u' under these tables

The reason must be a nonempty string. This guard checks that a reason was supplied, not that it is adequate or true; the caller retains it. The ports reject values outside the three strings. Results above describe this logic's unknown value. They do not disprove the laws of classical logic.

The compact four-line example on the website omits input validation. Use the repository ports when inputs are not already constrained to 1, 0, u. The same tape does not establish agreement on inputs absent from that tape.

A reproducible behavior fingerprint

In the order 1, 0, u, run not on each value, and on every pair, or on every pair, then check refusal of a bare u. The 22-result tape is:

01u10u000u0u11110u1uu1
sha256 = 66cce8d50854ee21b9964b5bdcb3aa80054f6da5e24de6258c268ea6e3942a35

66cce8d50854 abbreviates that digest. The measured tape is computed by running functions; KNOWN also stores the expected tape for comparison. PROVENANCE.md and the U page associate it with this project. This is a published association, not an automatic identity resolver or an author signature. Independent implementations can produce the same tape. Use the full digest when comparing records.

Burn and return

node burn.mjs removes comment lines and renames selected identifiers in the checked-in JavaScript implementation, preserving string literals. It executes the transformed copy and compares the tape. It uses a unique temporary folder and removes it on normal completion or a caught error. It does not prove that every transformation, language or future version preserves behavior.

The protocol's display burn is a separate mechanism: hide, rotate, both or neither, with a stated finite duration and an earlier Restore. Canonical provenance stays available. Neither mechanism guarantees anonymity, erasure, recovery of deleted code, or a delay before someone identifies a copy.

Licence and credit

LICENSE offers the published custom U Device License 1.0 and its published MIT alternative. The custom grant requires its licence and canonical provenance and specifies return/Restore for a display burn. The MIT option requires retaining its copyright and permission notice in copies or substantial portions. A code edit does not automatically remove applicable notice terms. The method is public; it is not a substitute for those terms.

Justichuu supplied the direction. Claude built the logic layer and consolidated the repository; Codex built the protocol and repaired the validation, checker and cleanup. The full contributor record keeps other contributions unknown where there is no supporting observation. See PROVENANCE.md.

Optional: developer checks

node u.js
python u.py
sh u.sh
node verify.mjs
node burn.mjs
node --test "test/*.test.mjs"
node build-browser.mjs --check

With Playwright installed, npm run test:browser checks the fish controls and the actual offline download. PLAYWRIGHT_MODULE may name an existing Playwright module file; BROWSERS=chromium,firefox,webkit selects all three engines.

To refresh an existing ChuuMind source copy, run node build-browser.mjs --site PATH_TO_SITE, then the same command with --check. It writes only this repository's browser build and the existing nav/u/run.html, preserving the site's data-proportion marker. It does not publish. The website's U explanation is maintained separately.

These developer commands need their named runtimes. They are not the entry point for using U. Set U_PYTHON or U_SHELL to an interpreter executable if it is not on PATH. The checker resolves its inputs relative to its own file, so it also works when called from another directory. Exit 0 means all listed ports agreed; 1 means a measured failure; 2 means no failure was seen but at least one runtime was unavailable. Missing is u; an installed runtime that exits with an error is 0.

[W] Continuation checked 24 September 2026 on Windows: Node 26.7.0, Python 3.14.7 and Git's POSIX shell produced the same tape. All 24 Node tests passed, including failed-runtime classification, use from another directory, cleanup, input validation, timed display return, receipt tampering, audio cancellation before resume and local-only voice selection. The exact checker also settled 3 + 3^2 + 3^2 + 1 = 22 by rational algebra.

[W] The browser entry and its actual download passed in Chromium, Firefox and WebKit on Windows at phone and desktop sizes, with no HTTP requests. Touch, keyboard, the finite table, four display modes, return and text receipts ran. A viewport is not a physical phone observation.

[U] Universal runtime support, physical adapters and authorship inferred from a tape remain unestablished. They require the relevant runtime/device observation or independent contribution evidence. CI and later releases add named snapshots; they do not establish all future behavior.

Repository history

[W] On 2 October 2026, the retired u-core and u-device folders were consolidated into this checkout on local branch nostalgia. Their original tips are merge parents; the current U implementation stays unchanged. Tags under history/u-core/ and history/u-device/ retain every original branch, remote ref and annotated release tag. For example, git show history/u-core/heads/main:u.py reads the original core. The original license versions remain in those histories.

[W] The unmerged perennial experiment remains on retained/perennial, outside the active product. Both existing linked worktrees remain in place; the former device worktree now belongs to this repository on legacy/u-device/codex/u-adapters. Its project files, index and reflog are unchanged.

[W] Original U reflog commits are pinned under history/u/reflog/; other loose recovery objects use local refs/local-recovery/u/objects/. Those local refs and the hash receipt in .git/consolidation/2026-10-02/ are not carried by a normal clone. No remote was updated during that consolidation.