Questions about Portage profiles and general installation

[notCarl]

Hey everyone. I'm a total linux noob. I've found myself in a situation where I'm this extremely broke student who needs an inexpensive hobby and is interested in learning linux.
I played around with Ubuntu and it seemed too bloated, and the whole reason I wanted Linux was to "hack" my own system in a DIY way(not a leet haxor). It reminded me of a retail OS. It even came with Amazon lol... Then I tried Fedora. Same thing.

Fast forward, now I'm halfway through installing gentoo, the unforgiving OS that I didn't want to hold my hand.

My question is in regards to the Portage Profiles. I am installing gentoo and learning linux because I want to get as close to possible to controlling my system as I can, and learn along the way. From what I understand, the profiles like Desktop/Gnome and Desktop/KDE include packages that are commonly used with systems running Gnome or DKE. Essentially saving time as well as preventing me from downloading packages I don't need, unlike Windows 10 which stuffs our system with bloatware.

Is the vanilla gentoo desktop package what I want as someone who wants to go through the process of building their system themselves for experience?
I do want it to be a desktop system. I've seen very cool desktop customization online that I'd like to try.(window managers, color, self scripted notifications)
If I were to install Gnome or KDE Profile (almost certain I will not), can I remove them at a later time and get my system to a similar build as if I had never chose the Gnome or KDE Profile?
I guess what I'm really asking is, does linux allow me to make changes to the settings I chose during installation at a later time? Do I really have that much control?
Will the Flags and USE Variables in the /portage/make.conf files have irreversible effects that I can not adjust after installation, or can I make adjustments as I learn?
Will anything during installation have irreversible impact on my system (other than setting up my kernel and partitions)

Any info is appreciated!
Thank you!

[NeddySeagoon]

notCarl,

Welcome to Gentoo.

The profiles set default USE flags for you. You then fine tune these defaults in the USE= statement in make.conf.
USE flags are Gentoos way of controlling optional functionality either globally (the profile or make.conf) or on a per package basis.

Profiles are a useful way of getting 90% of your use flags set the way you want/need without doing a lot of work.

You can put the special flag -* at the beginning of USE= in make.conf if you really want to. That turns off all USE flags.
Then its all up to you.

When you get it wrong, you change a USE setting and rebuild affected packages.

If you are a control freak, you can set all your USE flags on a per package basis. The choice is yours.
Shiny binary distros have already made these choices for you.
Gentoo is a toolkit you use to build your own distro. Gentoo is the Portage package manager and the ebuild repository. Everything else is $UPSTREAM

You can see what the profiles do. Choose a profile, then run

[John R. Graham]

To elaborate very slightly on what Neddy said:

[josephg]

[notCarl]

Thank you! The info is appreciated.

[NeddySeagoon]

notCarl,

Almost nothing you do in Gentoo is irreversible. There are a few things, like the recursive use of chmod or rm, done as root, on the wrong path that you really don't want to do.
Why, is left as an exercise for the reader.

You can probably get into a situation where backing out is difficult and the only reason to do it is for the educational experience.
In these situations, is often faster to reinstall. In general though, Gentoo does not respond well to reinstalling to fix problems.
That approach only gives you the opportunity to make a different mistake.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[cwr]

It might be worth looking at:

[John R. Graham]

[josephg]

thank you. that increases my confidence in gentoo stability. but for the amount of rubbish gnome pulls in, am i not better off wiping the slate clean and install from scratch or a previous backup?

[NeddySeagoon]

josephg,

~arch is quite usable. It will bite occasionally and without warning but its much more stable than it was.

At one time, there was arch, ~arch and masked packages. At that time development in overlays was fairly rare.
Today, most development has moved outside of the main repository into overlays. The result is that ~arch is more stable than it was.

If you really mean ~x86 because you have a 32 it install, stay with it. Few developers have 32 bit hardware any more, so stabilsing packages on x86 is slower than it once was.

There are some risk reduction measures you can take to avoid much of the pain of testing.

Update monthly
Read the emerge news items.
Pick an update time when if it goes wrong, you have time to fix it by backing out at least some of the change.
Turn on FEATURES=buildpkg, so you build up a collection of binary packages that you can use to back things out.
Learn about the -K flag to emerge.

I recall spending 8 hours building OpenOffice, only to have no icons when it opened and 10 minutes reverting the update by installing the previous binary.
That was on ~x86.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[josephg]

[NeddySeagoon]

josephg,

If I had to rebuild the old version, it would have been another 8 hours.

FEATURES=buildpkg saves a binary of every package that you build.
Eventually, you have binaries of everything you ever built successfully, so a revert is only an