Daeseon Yoo

A documentation + branding day: the user-facing name became JJAN! · 짠, and two grounded reference docs landed — a bilingual README and a troubleshooting index.

What

Three commits, all dated 2026-06-02:

A user-visible rebrand from "Ki Clash" to JJAN! · 짠 on the web app's public surfaces (6e6c090).
A comprehensive bilingual EN/KO README aimed at a recruiter or fellow engineer (36a525d).
A problem-indexed troubleshooting reference doc (31ae407).

Important distinction this post keeps straight: JJAN! is the user-visible brand; ki-clash stays the internal project/code slug. The rebrand deliberately touched only what a user reads, not the code identity.

Changes

Brand rename — 6e6c090 (brand: rename user-visible surfaces from "Ki Clash" to "JJAN! · 짠"). Four web files, +26/-8:

web/src/app/layout.tsx — page metadata title became "JJAN! · 짠", with a rewritten description and newly added openGraph / twitter (summary_large_image) card blocks (siteName: "JJAN!").
web/src/app/page.tsx — the lobby <h1> went from Ki Clash to JJAN with a yellow-accented ! (text-yellow-300) and a glow textShadow; the subtitle changed from 기싸움 to 짠 · 기싸움, and the tagline gained a "1-second reveal duel" lead-in.
web/src/app/shop/page.tsx — "Support Ki Clash" → "Support JJAN!".
web/src/app/invite/page.tsx — the navigator.share sheet title "Ki Clash Challenge" → "JJAN! Challenge", with new copy "Read me in JJAN! — 1-second 1v1 duel. JJAN!".

Per the commit body, the rename intentionally did not touch the invisible identifiers: Redis key prefixes (ki_clash:game:*, ki_clash:room:*, ki_clash:player:*), repo / package / module names, source-file header comments, and /api/v1/... API paths.

Bilingual README — 36a525d (docs: comprehensive bilingual README (EN/KO) — recruiter-ready overview). Replaced the placeholder one-liner with a full overview (README.md +385/-2, README.ko.md +373, 756 insertions total). README.ko.md is a translation of the same content, not a separate marketing pitch — the two cross-link (English · 한국어). The commit body lists repo-verified stats captured at write time (e.g. 93 commits, 36 fighter PNGs across 6 characters × 6 poses); per the project's zero-fabrication rule I'm citing those as the commit's own numbers rather than re-deriving them here.

Troubleshooting reference — 31ae407 (docs(troubleshooting): add grounded problem-indexed troubleshooting reference). New docs/troubleshooting.md (+100). It's a problem-indexed companion to this date-indexed timeline: 8 non-trivial fixes in Symptom / Cause / Fix / Commit / Pattern form (the PvP concurrency bugs, JWT 401 auto-recovery, Railway deploy fixes). The commit body notes an adversarial verify pass caught and corrected one fabricated cause before publishing.

Why

"Ki Clash" was generic and overlapped with existing Clash-named titles. JJAN (짠) is the Korean onomatopoeia for a surprise reveal — the sound you make uncovering something at the same instant, which is exactly the game's core moment ("3, 2, 1, JJAN!"). The name maps directly onto the mechanic.

Keeping the code slug as ki-clash is the deliberate part: a brand can change cheaply when it lives only in user-facing strings, but renaming Redis key prefixes, modules, and API paths is a migration with real blast radius. Separating the two means the rebrand is a 4-file string change, not a refactor.

The README and troubleshooting doc serve the recruiter-facing goal: a grounded, anti-fabrication overview someone can read in two minutes, plus a problem-indexed log that shows how concrete bugs were diagnosed and fixed.

Notes

The README title still reads "Ki Clash · 기싸움." The README commit (36a525d, 15:31) landed earlier the same day than the brand commit (6e6c090, 20:07), so it predates the JJAN! decision and was not retro-edited in this batch.
Domain plan (from the commit body, not yet provisioned): jjan.daeseon.ai as a zero-cost subdomain on the already-owned daeseon.ai, with a possible move to a dedicated domain later. The README's live link at this point is still kiclash.daeseon.ai.
The troubleshooting entries are cross-referenced to decision records — e.g. the spurious-opponent_reconnected fix cites DR-10 ("Single handle_connect() vs separate first/reconnect handlers"), the "tell, don't ask" / push-the-decision-into-the-callee pattern documented in docs/engineering-log.md.

Commits

6e6c090 — brand: rename user-visible surfaces from "Ki Clash" to "JJAN! · 짠"
36a525d — docs: comprehensive bilingual README (EN/KO) — recruiter-ready overview
31ae407 — docs(troubleshooting): add grounded problem-indexed troubleshooting reference