JS has gotten everywhere. It drives the UI of most of the apps created to run on the most accessible platform in the world (the web browser). It has been uplifted into Node and Electron for widespread use on the backend, on the command-line, and on the desktop. It's also being used for mobile development and to script IOT devices, too.
So how did we get here? Let's review history, do some programmer anthropology, and speculate about some sociological factors.
JS's birth and (slightly delayed) ascent begins roughly contemporaneous with its namesake—Java. Java, too, has managed to go many places. In the HN comments section in response to a recent look back at a 2009 article in IEEE Spectrum titled "Java’s Forgotten Forebear", user tapanjk writes:
Java is popular [because] it was the easiest language to start with
In the early 2000s in particular, this meant that you could expect to find tons of budding programmers adopting Java on university campuses, owing to Sun's intense campaign to market the language as a fixture in many schools' CS programs. Also around this time, you could expect its runtime—the JRE—to be already installed on upwards of 90% of prospective users' machines. This was true even when the systems running those machines were diverse. There was a (not widely acknowledged) snag to this, though:
As a programmer, you still had to download the authoring tools necessary for doing the development itself. So while the JRE's prevalence meant that it was probably already present on your own machine (in addition to those of your users), its SDK was not. The result is that Java had a non-zero initial setup cost for authoring even the most trivial program before you could get it up and running and putting its results on display.
Sidestepping this problem is where JS succeeded.
HTML and JS—in contrast to not just Java, but most mainstream programming tools—were able to drive the setup cost down to zero. When desktop operating systems were still the default mode of computing, you could immediately go from non-developer to developer without downloading, configuring, or otherwise wrangling any kind of SDK. This meant that in addition to being able to test the resulting code anywhere (by virtue of a free browser preinstalled on upwards of 97% of consumer and business desktops), you could also get started writing that code without ever really needing anything besides what your computer came with out of the box.
You might think that the contemporary JS dev ecosystem would leverage this—having started out on good footing and then having a couple decades to improve upon it. But weirdly, it doesn't work like that.
JS development today is, by far, dominated by the NodeJS/NPM platform and programming style. There's evidence that some people don't even distinguish between the NodeJS ecosytem and JS development more generally. For many, JS development probably is the NodeJS ecosystem and the NodeJS programming style is therefore seen as intrinsic to the way and form of JS.
In the NodeJS world, developers working in this mindest have abandoned one of the original strengths of the JS + browser combo and more or less replicated the same setup experience that you deal with on any other platform. Developer tunnel vision might trick a subset of the developers who work in this space into thinking that this isn't true, but the reality is that for NPM-driven development in 2019, it is. Let's take a look. We'll begin with rough outline of a problem/goal, and observe how we expect to have to proceed.
Suppose there's a program you use and you want to make changes to it. It's written for platform X.
With most languages that position themselves for general purpose development, you'll start out needing to work through an "implicit step 0", as outlined above in the Java case study. It involves downloading an SDK (even if that's not what it's called in those circles), which includes the necessary dev tools and/or maybe a runtime (subject to the implementation details of that platform).
After finding out where to download the SDK and then doing exactly that, you might then spend anywhere from a few seconds or minutes to what might turn out to be a few days wrestling with it before it's set up for your use. You might then try to get a simple "hello, world"-style program on the screen, or you might skip that and dive straight into working on the code for the program that you want to change.
Contemporary JS development really doesn't look all that different from this picture—even if the task at hand is to do "frontend" work meant to run in the browser—which was the predominant use of JS early in its lifetime, when it still did have zero setup cost.
I have a theory that most people conceptualize progress as this monotonically increasing curve over time, but progress is actually punctuated. It's discrete. And the world even tolerates regress in this curve. If engaged directly on this point, we'd probably find that for the most part any given person will readily acknowledge that this is the true character of that curve, but when observed from afar we'll see that most are more likely to appear as if in a continual motte-and-bailey situation with themselves—that their thoughts and actions more closely resemble that of a person who buys into the distorted version of progress, despite the ready admission of the contrary.
Steve Klabnik recently covered the idea of discrete and punctuated progress in his writeup about leaving Mozilla:
at each stage of a company’s growth, they have different needs. Those needs generally require different skills. What he enjoyed, and what he had the skills to do, was to take a tiny company and make it medium sized. Once a company was at that stage of growth, he was less interested and less good at taking them from there.
The corollary to Steve's boss's observation is that there's stuff (people, practices, et cetera) present in later phases and to which we can directly attribute the success and growth during that phase, but that these things could have or would have doomed the earlier phases. It seems that this is obviously true for things like platforms and language ecosystems and not just companies.
To reiterate: JS's inherent zero-cost setup was really helpful in the mid-to-late 2000s. That was its initial foot in the door, and it was instrumental in helping JS reach critical mass. But that property hasn't carried over into the phase where devs have graduated to working on more complex projects, because as the projects have grown in complexity, the tooling and setup requirements have grown, too.
So JS, where it had zero setup costs before, now has them for any moderate-to-large-scale project. And the culture has changed such that its people are now treating even the small projects the same as the complex ones—the first thing a prospective developer trying to "learn to code" with JS will encounter is the need to get past the initial step zero—for "setting up a development environment". (This will take the form of explicit instructions if the aspiring developer is lucky enough to catch the ecosystem at the right time and maybe with the help of a decent mentor, or if the aspiring developer is unlucky and the wind isn't blowing in a particularly helpful way, then it may be an implicit assumption that they will manage to figure things out.) And developers who have experience working on projects at the upper end of the complexity spectrum also end up dealing with the baggage of implicit step zero for their own small projects—usually because they've already been through setup and are hedging with respect to a possible future where the small project grows wildly successful and YAGNI loses to the principle of PGNI (probably gonna needed it).
Jamie Brandon in 2014 gave some coverage to this phenomenon on the Light Table Blog (albeit from the perspective of Clojure) in a post titled "Pain We Forgot".
To pull an example from the world of JS, let's look at the create-react-app README, which tells you to run the commands:
npx create-react-app my-app cd my-app npm start
What assumptions does it make? First, that you're willing to, able to, and
already have downloaded and installed NodeJS/NPM to your system; secondly,
that you've gone through the process of actually running
create-react-app, and that you've waited for it to complete successfully.
(You might interject to say that I'm being overly critical here—that by the time you're looking at this README, then you're well past this point. That's the developer tunnel vision I referred to earlier.)
Additionally I'll note that if we suppose that you've started from little more than a blank slate (with a stock computer + NodeJS/NPM installed), then creating a "hello, world" app by running the following command:
npm install create-react-app && npx create-react-app foo
... will cost you around 1.5 minutes (in the best cases) while you wait for the network and around half a GB of disk space.
If JS's early success in the numbers game is largely a result of a strength that once existed but is now effectively regarded as non-existent, does that open up the opportunity for another platform to gobble up some easy numbers and bootstrap its way to critical mass?
Non-JS, JS-like languages like Haxe and Dart have been around for a while and are at least pretending to present themselves as contenders, vying for similar goals (and beyond) as what JS is being used for today. And then there are languages nothing like JS, like Lua, which has always touted its simplicity. And then there is the massive long-tail of other languages not named here (and that possibly haven't even been designed and implemented yet).
What could a successful strategy look like for a language that aimed to displace JS?
- Skips the problems with contemporary JS development
- no implicit or explicit initial setup required
- avoids problems that have been referred to as "JS fatigue"
- Plays to JS's original strengths
- stupidly easy to go from zero to "hello world"
- insanely huge installed base
If you come from a JS background, you might argue that you still have the option of foregoing all the frameworks and tooling which have obviated JS's zero setup strength. As I alluded to before, though: rarely does anyone actually run a project like that. So while "hello, world" is still theoretically easy, the problem is twofold:
The "hello, world" lessons that learners have in front of them and that are pushed the most are more likely to be similar to the ones for create-react-app
While you can do your own thing, virtually no one today is going to clone an existing project and find anything other than the sorts of things I've described
Which is to say, that in either case as a developer, you're going to run into this stuff, because it's what people are pushing in this corner of the world. And therefore the door is wide open for a contender to disrupt things.
So the question is whether it's possible to contrive a system (a term I'll use to loosely refer to something involving a language, an environment, and a set of practices) built around the core value that zero-cost setup is important—even if the BDFL and key players only maintain that stance up to the point where the ecosystem has reached a similar place as contemporary JS in its development arc. Past this point, it would be a free option to abandon that philosophy, or—in order to protect the ecosystem from disruption by others—to maintain it. It would be smart for someone with these ambitions to shoot for the latter option from the beginning and take the appropriate steps early to maintain continuity through all its phases, rather than having to bend and make the same compromises that JS has.
I didn't set out when writing this post to offer any solutions or point to any existing system, as if to say, "that's the one!". The main goal here is to identify problems and opportunities and posit, Feynman-style (cf There's Plenty of Room at the Bottom), that there's low-hanging fruit here, money on the table, etc.