Background:
There’s a custom component to create adaptive lighting called circadian_lighting - the most popular custom component in HACS.
Bas Nijholt rewrote the custom component and created a PR for integration of his work into the core. This failed for various reasons.
Since the PR is already pretty lengthy in its discussion this thread aims to give you a place to discuss what points need to be addressed to get this feature into Home Assistant core.
I really hope this gets integrated fast. I have been waiting for the custom components for a year now and I have used both of the custom components without any problems.
I think this should be priority as people don’t even know they need this.
Hey @chiphead,
There’s not THAT much advantage of having this as an official component for the users as I guess most people use HACS anyway. 
It’s more important to fix bugs and include more features in the component - for example have a way to use fixed light color lamps to safe some money for the hardware
Well everybody does not use HACS and try to avoid using custom components. I don’t in my current config.
And if it is not custom component then it needs to be core component.
I don’t get it why you are against this.
And the thing is that it can effect how well you sleep
Never said that I’m against it, but the component needs a bit more work before it makes sense to integrate it IMHO.
Once integrated its a bit more difficult to develop stuff e.g. because of longer latencies for reviews of changes.
There was a PR open for a long time to include it as a core component and the team didn’t got to it
Yeah. So long that they lost interst
Have you had a look at flux? Flux - Home Assistant
PS: I can second that not everybody is using HACS. At least for non-HA-OS users (eg. Container) it’s not common.
Will this ever be revisited?
I’m not sure if the approach to make it a core component will be reevaluated. But according to GitHub information the author is currently working on the next major version of AL.
Being part of core imposes too much rules and very slow PR turnaround time, if anyone is interested to install the component, there is a way to do via hacs.
If you think, being part of core will make the integration more secure or up to date or maintained, that is not true. What is stored inside core is about integrating an external python package, not business logic. So, original dev should manage the external package on its own.
I tend to agree with you. When I look what happened with the Fritz!Box Tools integration (AVM FRITZ!Box Tools - Home Assistant) since it is part of Core… pretty much of a disaster - it’s the opposite of “stable” and you need to wait a very long time until bugs are fixed - cause the bugfixes are only shipped with HA Core releases.
So HA world is not black and white - there are pro’s and con’s to an integration being part of HA Core.