this was so easily explained. I remember reading an online article some time back but could understand nothing. Thank you Frederik!

I would strongly disagree with the notion, that the only difference between microservices and SOA is the size of the services, although it is true, that microservices are smaller. If your microservices call other services directly via http calls, you end up with a distributed monolith, because these services are now tightly coupled. This is something you want to avoid. As you point out, MS brings also organisational benefits, as every service can be developed and deployed (somewhat) independently. This is much harder to achieve, when they are coupled. Also deprecate, replace, or split an existing service is much harder, when there are dependent services. Microservices should only communicate via a message bus or, even better, event sourcing, like Apache Kafka. In that way, kafka is the only dependency the microservice has. In your example the user and book service would send a message for each user and book they create and update through the message bus. The orders service would then store a copy of the users and the books in its own database. Perhaps not the entirety of the object, just the properties it needs. As an additional benefit the orders service can serve the request much quicker, as it does not need to wait for the responses of the books and users service (which in turn could also call other services and so on)

Finally I understand why the different paradigms

I follow too many programming related youtube channels, and most of them just talk... I'm going to unsubscribe from them, because at this stage they are just a distraction. Thanks Fredrik, for actually educating me. You and my mentor are the only one's that showed me the real path.

I found your explanation really helpful! Saludos, from Argentina :)

Very clearly explained in a simple Language. Thanks Fredrik, keep it up!

I've been looking for this explanation all day. Thank you

Amazing! I am a new huge fan of yours! Thank you so much for showing the code to go with the explanations.

Great video, pretty sure you just completely cured my microservices FOMO

Very well explained. Thank you so much.

interesting topic and very good descriptions!

Great video, do you recommend some good book about SOA?

Well explained! Thanks.

Love it!

great video as usual, do you have some material suggestions about architecture for beginners?

It is really usefull!! thanks

SOA uses middleware as well, so that services can talk with one another, Micro-ervices dont need them. just API calls , also in Microservice architecture, each service has its own local DB, and these DBs are synchronised.

Would love to have more videos on SOA, like how do you choose how to split the monolith and how to deal with the network calls has @Dawid Dahl asked. I was pretty naive on this, thinking that async/await + errors would just be enough ...

Hey I am planning to develop a clash of clans style mobile game as a free time project , which among this 3 architecture will you recommend , Thank you

Great video, but i feel as if you have glanced over some of the major benefits of a distributed architecture (this includes SOA and MSA). What about scaling? Continuous integration and deployment? The developer experience might be greater / easier with a monolith, but there are also other organisational and business needs that are more important than this.

4:30 hasn't Sun pioneered cloud computing? why would you say that all they created was monoliths?

Where does ESB come in SOA?

Why SOA cant deploy independent ¿ In your example you could deploy Order.js without deploying the rest right?

Good except the title should have been CDN system design.