Many thanks for your time on this extended feedback, is very nice to read and know more about other supervisors and what is expected to accomplish with this kind of tools.

I apologize in advance because unfortunately, the current documentation of the project don't cover all cases and because of that, some assumptions can be made until going deep into the code or testing, I will try to clarify some point hoping I could transmit a better idea of what the goal was and how is working, so pease bear with me.

For example, there is a "down" option, same as the "once" options https://github.com/immortal/immortal/blob/9ed9087a8ef1e64d64...

Same with the enable/disable that in immortal is "start/stop" or also -x that is "exit"

You indeed can send a signal STOP, mainly because of this when using [immortalctl](https://immortal.run/post/immortalctl/) the option "stop" is used instead of down:

https://github.com/immortal/immortal/blob/master/cmd/immorta...

When following a pid, you indeed can still send signals to the "adopted PID" if we may call it that way.

Now immortal is totally capable of knowing the process ID of the daemon, but the methods you described as for reading PIDS from a file and checking if process are up and running, does methods are mainly used within the `-f PID` follow PID option in where you want to supervise or know status about a PID that the supervisor didn't create and, for this in BSD systems Kqueue is used instead of long polling https://github.com/immortal/immortal/blob/9ed9087a8ef1e64d64...

I have some animations here http://immortal.run/about/ maybe they are not very clear but hope they could clarify this.

In case you know a better way of knowing if a process exists, something like asked here: http://stackoverflow.com/a/15210305/1135424, I will be more than happy to implement it.

Regarding the login options, I would say it was the main motivation to create `immortal`, http://serverfault.com/questions/752839/how-to-make-svlogd-s..., these days dealing with microservices and try to follow a 12-factor approach force you to innovate, in this case the idea of delegating a logger to a 3rht party is because doesn't limit your options, for example, if you want you could just pipe directly to [filebeat](https://www.elastic.co/products/beats/filebeat) and at the same time continue writing files to disk and rotate them.

The idea of not using link files was to simplify more the process, is true that while writing to the file there could be some issues, I will have to check/test more in detail, but the approach I took, was to keep checksum of the files to guarantee integrity and also based on the atime take actions: https://github.com/immortal/xtime, not perfect probably but is a start.

Regarding the portability, I think currently I am bound to the output and systems in where [xtime](https://github.com/immortal/xtime) could work, so basically, limits to, Darwin, FreeBSD, Linux, Dragonfly, NetBSD, OpenBSD,

Regarding the web server, the idea came by accident and I would say that thanks to the power of [go](https://golang.org/) this became very handy, mainly because daemontools/runit use named pipes for controlling the processes, but since they are not bi-directional you need two pipes, now the idea of using a Unix socket, is because they are bi-directional, therefore you just need one file and by "accident" you just inherit a nice capability that allows you to interact via HTTP with the socket.

http://immortal.run/post/nginx/

And well, for sure more work and improvements need to be done, including the bad documentation that may cause bad impressions about what really is wanted to be solved and cover.

One again thanks for your feedback and time on this, maybe we could use https://github.com/immortal/immortal/issues for special issues.