I’ll introduce what I researched about the Leaky Bucket algorithm.
Background: Shopify API Adopts the Leaky Bucket Algorithm
The leaky bucket algorithmAll Shopify APIs use a leaky bucket algorithm to manage requests. This algorithm lets your app make an unlimited amount of requests in infrequent bursts over time.
Quote from: The leaky bucket algorithm - Shopify API rate limits
List of Reference Articles on Leaky Bucket Algorithm
Here’s a list of articles I read to understand the Leaky Bucket algorithm:
Wikipedia's Leaky Bucket
The Japanese Wikipedia version of “Leaky Bucket” is written simply, so if you want to know more details, please read the English Wikipedia version of “Leaky bucket”.
Leaky Bucket Implementation Case Studies
There was a case where PAY.JP adopted the leaky bucket algorithm for introducing Rate Limits, so I read these articles as well.