HomeComputer ScienceFeature-Flag Rollout Bucketing Simulator

Feature-Flag Rollout Bucketing Simulator

Interactive 3D simulator of the deterministic hash-bucketing algorithm behind mobile remote-config and feature-flag percentage rollouts — watch sticky consistent-hash bucketing stay monotonic while naive per-user coin flips churn users on and off.

Computer Science3DModerate60 FPS📱 Mobile-adapted
mobile-configuration-management ↗ Open standalone

Every mobile app that ships a "rolled out to 25% of users" remote-config flag is running the same small algorithm: hash each device's stable user ID together with the flag's salt into a bucket from 0–99, then flip the flag on if that bucket falls under the target percentage. This simulator renders a population of users as a live 3D grid and lets you drag the rollout percentage while toggling between that real sticky, consistent-hash bucketing and a naive per-user coin flip re-rolled on every change. With sticky bucketing on, raising the percentage only ever turns more users on — the "consistency violations" counter proves it stays at zero. Switch it off and watch users flicker in and out even as the percentage rises, the exact bug class a hash-based rollout is built to avoid.

⚙ Under the hood

An interactive 3D population of app users shows the deterministic hash-bucketing algorithm behind mobile remote-config percentage rollouts, contrasting sticky consistent-hash bucketing (monotonic, no flip-backs) with a naive per-user coin flip that churns users on and off.

feature flagsremote confighashingrolloutmobilea/b testing

3D · Three.js / WebGL renderer · 60 FPS target · runs fully client-side, no install

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