Recommendation for Free Lazy Loading Extensions Magento 2

i’m looking for recommendation for free lazy loading extension that is likely works for magento 2.2.9 with infortis ultimo theme.

here are some list i found:

-welt MAGENTO 2 LAZY LOAD PRODUCTS AND IMAGES.

-bss Magento 2 Lazy Load

-magezon Magento 2 Lazy Load Extension

-Magento 2 Image Lazy Load Extension

have anyone try any of them, and recommended or not recommended?

Help! I need a link spying tool… recommendation urgently

Hi,
I am Alvin a junior marketer that wants to specialize in SEO. I am looking for a tool that could spy on the links created by my competitor. I need to have a record of when the link is built and when the link is dropped. Ahrefs and Sem rush doesn't have that and its fairly inaccurate for link building. Does anyone of you have any recommendations? Any help given is deeply appreciated.
Cheers
Alvion

Designing Recommendation Engine with Elastic Search

My end goal is to serve an app where the user can do through a bunch of docs: if the like a document, they see another document similar to the one they liked…if they like that one, they see another on – and so on.

I’m planning to store all of these docs in an elastic search instance. Every day, I’d insert 100 documents via a cronjob at a given time.

Upon insertion of a single document, d, I would also compute how similar is to all existing documents. I would create a new field called most_ similar_to in d and it would be a list of pointers to the other similar documents.

The advantage to the above approach is that the end user doesn’t have to “wait” for my app to find similar docs, as it’s already cached.

How can I improve on this design? It’s a simple server, with no concurrency or anything.

Architecture/algorithm for unusual recommendation system

There are thousands (or tens of thousands) of possible movie titles. New user enters my website and selects hundreds of titles that he likes.

The only single goal of my website is to output the list of other users that liked exact same titles, but with only very minor differences – say, only 1-5 titles between users are different.

The solution I see is straightforward – take input from new user, iterate over every row in database to compare it with every other user, output the result.

But I want to solve it with millions (or tens of millions) of users in mind – and the straightforward solution of course doesn’t scale well at all.

I feel like maybe my lack of formal education with algorithms/data structures is limiting my thinking here – how could I implement a more efficient solution?

Note that I don’t want to categorize users in vague buckets that have common interests – I want to match exact titles between users as precisely as possible – so it’s not your usual common recommendation system, I guess.

Recommendation for user synchronization between organization and external website

We are building a small social media platform for collaboration among a group of similar (but disparate) organizations. Each organization will have a small group of users who will be able to post content on this platform.

What would be the recommended ways for these users to create accounts on our social media platform? Our primary concern is if any member of the group leaves the parent firm, then his access should be revoked immediately from the platform too. He/she would obviously know the credentials, since he/she was a part of the entitled users earlier.

We are planning to host our platform on a cloud provider like MS Azure or AWS.

Thanks in advance