Update: I apparently missed the line about going to my application's root directory. I still didn't really like all the stuff that got downloaded and compiled on my machine, when all I would like to do is get started developing.
I'm a Phusion Passenger developer. The goal for Phusion Passenger Standalone really is to have the command 'passenger start' Just Work(tm). After installing all required libraries, if it says it's running on port 3000 and it doesn't, then it's either a bug which we are dedicated to fix, or there might be something wrong with your system.
The 'file-tail' thing is actually a bug (we should no longer have a requirement on file-tail). We've already fixed it in git master 3 days ago and the fix will be released very soon.
Can you give me some more details about the 403 error? Do you see anything in the console or in the browser window that tells you more about the error?
Sorry :( I made a reading error and I updated my post.
It still seems like a lot of software and time to just start developing. What does passenger get me for developing locally that Pow doesn't? (I've never used Passenger before today).
I can't comment on how Phusion Passenger Standalone differs from Pow because I've never used Pow. However I can tell you what Phusion Passenger Standalone's benefits are:
1. Phusion Passenger is currently the most popular production server for Ruby web apps (see ruby-toolbox.com and the last NewRelic survey). Phusion Passenger Standalone is practically the same as Phusion Passenger for Nginx. It's a good thing to have the development environment match the production environment as much as possible. Phusion Passenger actually comes in 3 editions: Phusion Passenger for Apache (integrates into Apache), Phusion Passenger for Nginx (integrates into Nginx) and Phusion Passenger Standalone (can run by itself, does not require an external web server).
2. Because Standalone is based on an Nginx core it's even fit for production. According to the Pow website it uses Nack, which according to its website is not ready for production. If 'passenger start' works for you locally then you can run the same thing in production. No need to learn how Apache and Nginx works.
There are other things as well, but I have to go in a few minutes. Feel free to ask me more questions if you like.
As for "the stuff that got downloaded and compiled on my machine", that's Nginx being downloaded and compiled there. Nginx is a high-performance, lightweight, extremely stable, battle-tested and proven web server.
Hypothetically speaking, it's possible to modify Phusion Passenger to not download and install Nginx. We can run on a pure-Ruby web server like WEBrick. However I guarantee you, WEBrick sucks; it's slow, buggy and leaks memory.
When this finished, I got an error and it all failed: "* ERROR: Please install file-tail first: sudo gem install file-tail"…
So I did and now its supposedly running on Port 3000 except I just get a 403 error when I visit it in my browser. The docs aren't very helpful either (http://www.modrails.com/documentation/Users%20guide%20Standa...).
Update: I apparently missed the line about going to my application's root directory. I still didn't really like all the stuff that got downloaded and compiled on my machine, when all I would like to do is get started developing.