Ask HN: Are any new systems *not* event sourced and microservices? | Hacker News Reader

Ask HN: Are any new systems not event sourced and microservices?

At present, it seems that every new system being spun up follows the event sourced / microservices pattern. I've heard the case made from many different corners. Cool though they are, this design tends to lead to increased complexity / cognitive load at an early stage.

It got me wondering, are people out there spinning up new systems and internationally not following that pattern?

I'm trying to understand if a sea change in architecture has occurred or whether I'm in a bubble and not appreciating all the different approaches that are generally being used in the industry today.

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You're right about microservices, but IMO you're mistaken Event Sourcing (CQRS/ES)[1,2] with EDA (Event-Driven Architectures)[3] in general.

There are many different types of EDAs.

There are at least 3 relevant dimensions when choosing a Software Architecture:

1. complexity of the domain

2. scalability requirements

3. company stage / number of developers working on the same codebase

Microservices are mostly solving #3, and to a lesser extent #2. They mostly solve the problem of too many developers blocking each other on a monolithic codebase (NOTE: monolithic doesn't mean non-modular).

Event Sourcing and friends (DDD, CQRS, EventStorming, etc.) are mostly solving #1. It's also technology/vendor-agnostic, so makes migration to other tech (including microservices) easier, and most importantly possible at all.

So for a complex domain in a small company I would choose a CQRS/ES monolith, but for a simple domain and high scalability in a large company maybe CRUD-based microservices are making more sense.

[1] https://martinfowler.com/eaaDev/EventSourcing.html

[2] https://martinfowler.com/bliki/CQRS.html

[3] The Many Meanings of Event-Driven Architecture • Martin Fowler • GOTO 2017

https://www.youtube.com/watch?v=STKCRSUsyP0

What do you mean by “Event-Driven”?

https://martinfowler.com/articles/201701-event-driven.html

tagged by: event architectures

https://martinfowler.com/tags/event%20architectures.html

Short answer: yes.

Long answer: The problems with distributed systems are plenty and are only worth it if the distribution itself is a key feature, because for example your system has to scale for millions of users around the world.

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