The following are examples of the four types rate limiters discussed in the accompanying blog post. In the examples below I've used pseudocode-like Ruby, so if you're unfamiliar with Ruby you should be able to easily translate this approach to other languages. Complete examples in Ruby are also provided later in this gist.

In most cases you'll want all these examples to be classes, but I've used simple functions here to keep the code samples brief.

This uses a basic token bucket algorithm and relies on the fact that Redis scripts execute atomically. No other operations can run between fetching the count and writing the new count.

Here be some of my notes on how to plan your CS career (specifically NUS).

First things first, I encourage you to have your own module plan (say, in a Google Sheets). You can start with the suggested module plan, but they are quite generic and might not suit your personal goals (e.g. some advanced modules you'd like to take have prerequisites that are offered in odd semesters only).

Having your own module plan will also make you easier to include other non-academic activities too.

• Take as many foundational (core) modules while you can. You never want to be left behind due to missing prerequisites.