Does anyone know where i can buy a custom built algorithm?

So basically i am looking for a custom built algorithm that can rank listings by number of signups over X amount of time. Those with less than Y will be ranked further to the top.

From how you describe it, any basic developer can do this.

1. Loop over the list of listings.
2. For each entry, calculate signups / time for whatever unit of time you have/want.
3. Insert the entry in a new, sorted list.

Bonus points if they know how to use transducers.

I agree with the other post that this is a fairly easy thing for any programmer. The devil is in the details--and if you're leaving any out it can get trickier-- but otherwise a developer should be able to handle this.

You don't need to order this from a developer or firm as "I need a custom built algorithm" just be like "I want a list sorted like such and such" and they should be able to handle this case for you at a quoted price

I think it's quite hard to do it, while you need to know a lot of variables to get it perfect for your scenario (ex. data source, types of data, language, framework, etc).