Back to Blog · July 20, 2026 · Engineering
How MOMENT verifies every ranked run
Most browser game leaderboards work on the honor system: the game says "I scored 40" and the server writes 40 into a table. MOMENT's global One Life board never takes the game's word for it. Before a single level counts, the server replays your entire run.
The honor system fails for a boring reason. A browser game ships all of its code to the player, so anyone who opens the developer console can call the same function the game calls and submit any score they like. If a leaderboard is worth reading, the score has to be proven, and the only proof a physics game can offer is the play itself.
It starts with a ticket
When you press the ranked One Life button, the game asks the server for permission to start, and the server answers with a ticket: the seed of the current season's course, the course version, and a one-time run ID. This has a nice side effect for fairness. Every ranked player on a season is playing the identical sequence of levels, because the level generator is deterministic and everyone is handed the same seed. The board compares like with like.
The run ID matters too. It can be used once, expires if unused, and pins the submission to a course the server itself issued. You cannot rank a practice run, a shared course, or a run from last season, however good it was.
The server plays your run again
While you play, the game records your actual movement path, level by level. When the run ends and you submit, that path travels to the server, and the server does something unusual for a small web game: it runs the same physics the game runs, feeding your recorded movements through the same level generator, the same collision rules, the same world-flow arithmetic, including all of the newer hazards.
Whatever the simulation says is what happened. If your movements genuinely clear twelve levels, the simulation clears twelve levels and you rank twelve. If the trace claims a crossing the physics does not allow, teleports even a pixel, or survives a hit the rules say connects, the submission is rejected. A forged score would have to be a movement path that actually beats the game under its real rules, at which point it is not a forgery. It is a run.
What gets stored, and what does not
Your raw movement path is processed for verification and then discarded. What the database keeps is a SHA-256 fingerprint of the trace, which exists for one purpose: the same replay can never be submitted twice. Copying someone's winning run byte for byte does not work, because its fingerprint is already on file.
The board itself stores the minimum a leaderboard can store: your chosen nickname, your best cleared-level count, and when you achieved it. Ranking uses cleared levels alone, and equal levels share a rank. Movement pixels and play time never break ties, so there is no incentive to grind an unpleasant statistic. You can also delete your own entry at any time from inside the game.
Seasons, versions, and why old boards close
MOMENT's rules evolve. When an update changes how levels generate, such as the one that added pulse lasers, mines, and dashers, comparing new runs against scores set under the old physics would be meaningless. So ranked play is organized into seasons, each pinned to one course and one version of the rules, with exactly one season active at a time. A rules change closes the old board with its records preserved and opens a fresh one.
The server keeps the ability to verify several rule versions at once. That detail sounds bureaucratic until the day an update rolls out gradually: a player on a cached older page can still finish and submit a legitimate run, and the server still knows exactly which physics their run must be checked against.
What this does and does not prove
Full replay verification proves that every ranked score corresponds to a physically real, rule-abiding run on the correct course. It deliberately does not try to prove who, or what, was holding the mouse. That is an arms race no browser game wins on the client side, and we would rather be honest about the boundary than pretend it away. What the board guarantees is narrower and, we think, more valuable: nothing on it is invented. Every number was played.