UML diagram for the DDD example in Evans' book • Hacker News Board

Re: UML diagram for the DDD example in Evans' book

#21

Post by hmartin » Fri, Apr 18, 2025, 10:30 PM UTC

titaphraz wrote: post #16

ak_111 wrote: post #2

What happened to UML? I remember it was everywhere in enterprise computing 20 years ago but seems to have disappeared now. Is it still around or did it go the way of SOAP, Java Applets? If not, what has replaced it?

UML was a scam really. They took a lot of very useful diagrams and created a absolute behemoth of unproven system to develop software and sold it. The diagrams are very nice and useful. But the UML as a process, if taken literally, it a total disaster.

> UML was a scam really.

Objectively and utterly wrong.

Re: UML diagram for the DDD example in Evans' book

#22

Post by firesteelrain » Fri, Apr 18, 2025, 10:42 PM UTC

These diagrams make a lot of sense if you understand the symbols and the relationships plus aggregations. You can easily talk to them. I use these diagrams with non technical people all the time

Re: UML diagram for the DDD example in Evans' book

#23

Post by icedchai » Fri, Apr 18, 2025, 10:55 PM UTC

whartung wrote: post #14

ak_111 wrote: post #2

What happened to UML? I remember it was everywhere in enterprise computing 20 years ago but seems to have disappeared now. Is it still around or did it go the way of SOAP, Java Applets? If not, what has replaced it?

I think folks upgraded to GML [0] [0] https://wiki.c2.com/?GalacticModelingLanguage

I love it. Even with GML, you run into problems. Diagramming is an art more than a science. You have to know your audience (technical people, marketing types, investors, customers...)

Leaving stuff out is also important. (Example: Unless you're building a DNS related product, don't bother to include "DNS" in your diagrams. Your use of it is assumed.)

Re: UML diagram for the DDD example in Evans' book

#24

Post by ohgr » Fri, Apr 18, 2025, 11:03 PM UTC

ak_111 wrote: post #2

What happened to UML? I remember it was everywhere in enterprise computing 20 years ago but seems to have disappeared now. Is it still around or did it go the way of SOAP, Java Applets? If not, what has replaced it?

UML never matched reality and this isn’t really an engineering discipline even if we pretend it is.

You can really break UML by specifying a system then changing it a number of times. That process will hurt you. Badly.

Re: UML diagram for the DDD example in Evans' book

#25

Post by alganet » Fri, Apr 18, 2025, 11:07 PM UTC

Good UML is really simple UML.

"Then what about complex things? Can't make everything simple"

Do partial diagrams. Simplify or skip things your team already knows.

Also, great UML is no UML. Sometimes the code itself is short and clear enough, requiring no diagram (of course, not all diagrams are about code... but use case diagrams are rare these days anyway).

Also, use cases and use case diagrams are great.

Also, perfect UML is disposable. Thinking of long term diagrams that serve as documentation is a mistake.

Re: UML diagram for the DDD example in Evans' book

#26

Post by wpollock » Fri, Apr 18, 2025, 11:31 PM UTC

fuzzer371 wrote: post #18

karlgkk wrote: post #11

Apropos of nothing, all of the major ai models have gotten really good at turning a pdf or document into uml Not great, mind you. 80% of the way there still saves an hour of your time tho

How about we ditch the AI slop

Have you noticed that at the bottom of every HN comment page is an ad for AI Startup School?

Re: UML diagram for the DDD example in Evans' book

#27

Post by afpx » Fri, Apr 18, 2025, 11:40 PM UTC

dcminter wrote: post #7

ak_111 wrote: post #2

What happened to UML? I remember it was everywhere in enterprise computing 20 years ago but seems to have disappeared now. Is it still around or did it go the way of SOAP, Java Applets? If not, what has replaced it?

I'm kind of hazy about where the boundaries between bona fide UML and PlantUML are, but PlantUML is in pretty common use in my world - more for sequence diagrams and state diagrams than class diagrams though. Of course PlantUML has competition from things like Mermaid, but they're all much of a muchness. My very non-scientific impression is that tools like Rational were mostly used for drawing class diagrams and ...…

I remember having to use Rational Rose back in the day, and I had to ask my boss why because the software crashed and the files got corrupted all of the time. If it didn’t help them write better software, why were we using it?

That said, I still find plantuml to be helpful, particularly for sequence and activity diagrams. With LLMs especially. Use dependency injection, fine granularity components, sequence and activity flows. At least for me, helps keep my mind organized. But, these days I work alone. I feel it may be too dated for the modern developer.

Re: UML diagram for the DDD example in Evans' book

#28

Post by SanjayMehta » Sat, Apr 19, 2025, 12:49 AM UTC

riffraff wrote: post #4

ak_111 wrote: post #2

What happened to UML? I remember it was everywhere in enterprise computing 20 years ago but seems to have disappeared now. Is it still around or did it go the way of SOAP, Java Applets? If not, what has replaced it?

UML as a methodology seems to have disappeared, but bits of it (e.g. sequence diagrams) seem to have been absorbed by the profession at large.

Sequence diagrams existed prior to UML. They were extensively used in telecom: “message sequence charts.”

They were part of a telecom language called SDL. There were tools to “compile” to various languages such as C. If you followed their rules, you were supposed to be able to go back and forth between C and SDL.

I only remember this because the biggest tool provider at that time was a French company called Verilog. They preceded the HDL by a few years, I guess.

Re: UML diagram for the DDD example in Evans' book

#29

Post by hirvi74 » Sat, Apr 19, 2025, 1:01 AM UTC

ak_111 wrote: post #2

What happened to UML? I remember it was everywhere in enterprise computing 20 years ago but seems to have disappeared now. Is it still around or did it go the way of SOAP, Java Applets? If not, what has replaced it?

My theory is that Agile killed it. UML requires a lot of planning up front, and in my unfortunate experience, any sort of planning is completely antithetical to Agile.

Re: UML diagram for the DDD example in Evans' book

#30

Post by 4b11b4 » Sat, Apr 19, 2025, 1:14 AM UTC

hirvi74 wrote: post #29

ak_111 wrote: post #2

What happened to UML? I remember it was everywhere in enterprise computing 20 years ago but seems to have disappeared now. Is it still around or did it go the way of SOAP, Java Applets? If not, what has replaced it?

My theory is that Agile killed it. UML requires a lot of planning up front, and in my unfortunate experience, any sort of planning is completely antithetical to Agile.

Experiencing this right now, zero planning for a re-write of a system