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Cover image for A shortening horse racing price is one of the oldest tells in betting. I built something to catch it before the off.
0xGollum
0xGollum

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A shortening horse racing price is one of the oldest tells in betting. I built something to catch it before the off.

Pari-mutuel odds aren't set by a bookmaker - they float with the betting pool right up until the race starts. When real money lands on a horse, its implied probability jumps and the price shortens, fast. By the time a human notices, the move is usually half over.

This actor watches every PMU (France's official pari-mutuel operator) race still open for betting and flags that movement as it happens: a steamer when a horse's implied probability jumps between runs, a drifter when it fades. Only races with an active status get scanned - anything already off is skipped automatically, so every run does useful work.

The data source is PMU's own public JSON API - the same one their website and app use, no key, no login, no proxy. As an opt-in extra, the actor can also flag hidden form patterns per horse: a jockey switch on the day, a horse still winless after ten-plus starts, earnings swinging sharply year over year - things a human would normally have to cross-reference by hand to catch.

https://apify.com/0xgollum/horse-racing-pulse

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