I disagree. My company (ePantry) has only hundreds, not thousands, of distinct products, but making recommendations is incredibly important. Showing users the r

I disagree. My company (ePantry) has only hundreds, not thousands, of distinct products, but making recommendations is incredibly important. Showing users the right product at the right time ensures they get the items they want, and it moves the needle on average basket size. I tried a number of off-the-shelf recommendation systems, none of which worked for the comparatively dense matrix we have (since we only have a few hundred products). I finally rolled one in house which took a few days of work (thanks, redis!) and has a bunch of custom filters that OTS systems wouldn't ever have. I hate building stuff like this when OTS is available, but everything was overkill, or too hard to configure, or initially gave bad results and required too much black-box tweaking. It's been a success and was way easier than I thought.