HomeAlgorithms & AIExperiment Bucketing: Deterministic Hash Assignment

Experiment Bucketing: Deterministic Hash Assignment

Interactive 3D simulation of how mobile A/B test frameworks assign users to variants: deterministic hash bucketing keeps existing users stable as you ramp traffic up, while naive re-randomization flips them every time.

Algorithms & AI3DModerate60 FPS📱 Mobile-adapted
mobile-ab-testing-implementation ↗ Open standalone

Behind every mobile A/B test sits a simple but easy-to-get-wrong mechanism: how do you decide, consistently, which variant a given user sees? This simulation renders 900 experiment "buckets" as a 3D grid and lets you ramp a treatment allocation up and down while comparing two real implementation strategies — deterministic hashing of a stable user ID (the correct approach used by production feature-flag systems) against naive re-randomization on every change (a real bug pattern that silently reshuffles already-running users). Watch how a hash-based rollout only ever grows the treatment group without disturbing users already assigned, while the naive approach flips large swaths of the grid on every ramp change, and use the "new experiment" control to see why two concurrent tests need independent salts to stay statistically uncorrelated.

⚙ Under the hood

A 3D grid of 900 experiment buckets shows how mobile A/B test frameworks assign users to variants: deterministic hashing of a stable user ID keeps existing users stable as you ramp traffic up, while naive re-randomization flips huge swaths of users on every change.

A/B testinghashingfeature flagsexperimentationalgorithms

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

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