Could you be more explicit, perhaps with an example? Do you simply mean you prefer function/constructor parameters over DI?
Benefits:
Unbelievably fast startup time
No magic
No annotations, XML or YAML required
No classpath scanning related security vulnerabilities
Conpletely deterministic
In no other language is ‘calling a constructor’ considered so complicated a framework is required.
Try it!
It does help to keep services small so the manual DI arg passing doesn’t get too spread out and boilerplate-y. But I have worked on a dozen services here and don’t miss an automatic DI framework.
I think it helps if you are building test/fakes of your deps that don't really need as many sub-dependencies. Generally you in a test `@BeforeAll` construct a bunch of objects or for a program you do it in `main`.
I did work on a project while I was at Google that was really big and a decade old that instead had a class with a bunch of lazy getters for each item in the dependency graph, then tests would override or reset the getters with testing versions as needed. It was a little clunky but I preferred that approach over the projects I worked on that used dagger.
If you've read through the Dagger dev-guide [0] there is *a lot* in there, while the manual approach it's usually just `new` which is a really simple concept on it's own :) I think this is the right tradeoff because reading code is harder than writing code, so it's worth the extra setup. In practice I haven't seen it to amount to be an overwhelming amount.
This feels like the sane thing to do, but sadly for historical reasons this won't work with many (if not the most) Java frameworks out there, or even certain options in the .NET ecosystem.
When you get non-trivial frameworks that are deeply entrenched in having DI and using it internally for a bunch of stuff, you'll find yourself out of options, e.g. if you use Spring/Spring Boot.
And in many places something like Spring Boot might be considered an "industry standard" and you might get looked at funny if you suggested using another framework, even more so if they have their own configuration/plugin/utility solutions for it already built within the org.
Personally, however, I rather enjoy alternative takes on how web frameworks could look and even something like Dropwizard/Vert.X/Quarkus have nice quality of life aspects to them.
In a sense, it's nice that the industry is moving towards smaller service based architectures, where you might spin up a new service with whatever tech fits the problem that you're trying to solve, as opposed to being locked into adding code on top of some bloated monolith (though that comes with certain tradeoffs and drawbacks, in regards to complexity and maintenance).