Live2026 · Solo Builder· Started(First Commit date) 2026-05-05

119 Challenge

A timing-sense game where you stop exactly at 11.900 seconds - an MVP for an SKKU EMBA event.

Screenshots

Entry screen - the one-line rule ("stop as close to 11.900 as you can") and a name field, nothing else
Name confirmation - a typo becomes the leaderboard and prize name, so we confirm once
Right before start - only the 11.900 target shows, with a single start button
Mid-attempt - the "focus" copy plus a large timer; the stop button stays pinned at the bottom
Result - the gap from 11.900 (0.009s), the score (9,991), and the grade (S) on one screen
Ranking - 1st/2nd/3rd podium with a personal-best alert; live updates so you see the next seat break a record

Setup

Problem: Needed a short, intuitive game that pulls people into an offline event. A long rule explanation breaks the queue.
Context: A fast MVP built for on-site use at a grad-school (SKKU EMBA) event.

What I did: Single-interaction game where you stop as close to 11.900 seconds as possible
Real-time ranking, podium, and record-broken alerts
Product decisions: Rules in one line ("stop at 11.900") - first-entry friction near zero
Live ranking updates - the moment the person next to you takes the lead is the trigger to try again
QA considerations: Measurement accuracy is trust - the client clock isn't taken at face value; the server re-validates against its own baseline
Under concurrent live-ranking updates, rank and personal-best decisions stay consistent without race conditions
Since a name typo becomes the leaderboard and prize name, the pre-submit confirmation step works reliably
Even if the on-site network drops for a moment, submissions and ranking recover so the "queue doesn't break" reliability of a live offline event holds
The gap (0.009s), score, and grade compute to the same result for the same record every time, so participants never doubt the verdict

Metrics: Used multiple times on-site at the event; exact participant numbers not collected.