Discussion on: As a non-web-developer, which are the things you'd like to learn to become a web developer?

Bit of a different perspective here, I am (mostly) a systems developer (that is, low-level userspace type stuff, sysops and netops tools, etc), and last December i decided to jump off the deep end into web development for an app I wanted to write. I don't know that I'll be changing careers, but I have liked it so far (mostly, I curse the JavaScript standards committees on a semi regular basis under my breath for the questionable choices that have been made over the years).

The two biggest selling points for me were (and still are):

• Contrary to popular belief, the web is actually insanely portable compared to most things. Java's touted 'write once run anywhere' mantra seems like a hollow promise in comparison. Pretty much, as long as you don't need to care about IE or Opera Mini, and can take the bit of effort to work around weird iOS crap, you can literally write code without issue that runs on everything by just paying a bit of attention to what you are choosing to use. This level of portability is a large part of what won me over for this project when compared to anything else I had similar levels of experience with.
• Your users need exactly zero extra libraries or software to run things you write. Everybody has a web browser, and you can even count on it being reasonably up to date most of the time, unlike things like Python (my main language of choice outside of web development). In fact, you don't even need an installer provided you write a PWA and make the service worker sane. Sometimes it may make sense to have a local install, but for a lot of things, it really doesn't (many social media sites don't really need native clients for example).