XSLT – Native, zero-config build system for the Web

I have worked for a company that (probably still is) heavily invested in XSLT for XML templating. It's not good, and they would probably migrate from it if they could.

  1. Even though there are newer XSLT standards, XSLT 1.0 is still dominant. It is quite limited and weird compared to the newer standards.

  2. Resolving performance problems of XSLT templates is hell. XSLT is a Turing-complete functional-style language, with performance very much abstracted away. There are XSLT templates that worked fine for most documents, but then one document came in with a ~100 row table and it blew up. Turns out that the template that processed the table is O(N^2) or worse, without any obvious way to optimize it (it might even have an XPath on each row that itself is O(N) or worse). I don't exactly know how it manifested, but as I recall the document was processed by XSLT for more than 7 minutes.

JS might have other problems, but not being able to resolve algorithmic complexity issues is not one of them.

It's generally speaking part of the problem with the entire "XML as a savior" mindset of that earlier era and a big reason of why we left them, doesn't matter if XSLT or SOAP or even XHTML in a way ... Those were defined as machine language meant for machine talking to machine, and invariably something go south and it's not really made for us to intervene in the middle; it can be done but it's way more work than it should be; especially since they clearly never based it on the idea that those machine will sometime speak "wrong", or a different "dialect".

It looks great, then you design your stuff and it goes great, then you deploy to the real world and everything catches on fire instantly and everytime you stop one another one starts.

> It's generally speaking part of the problem with the entire "XML as a savior" mindset of that earlier era and a big reason of why we left them

Generally speaking I feel like this is true for a lot of stuff in programming circles, XML included.

New technology appears, some people play around with it. Others come up with using it for something else. Give it some time, and eventually people start putting it everywhere. Soon "X is not for Y" blogposts appear, and usage finally starts to decrease as people rediscover "use the right tool for the right problem". Wait yet some more time, and a new technology appears, and the same cycle begins again.

Seen it with so many things by now that I think "we'll" (the software community) forever be stuck in this cycle and the only way to win is to explicitly jump out of the cycle and watch it from afar, pick up the pieces that actually make sense to continue using and ignore the rest.

A controversial opinion, but JSON is that too. Not as bad as XML was (̶t̶h̶e̶r̶e̶'̶s̶ ̶n̶o̶ ̶"̶J̶S̶L̶T̶"̶)̶, but wasting cycles to manifest structured data in an unstructured textual format has massive overhead on the source and destination sides. It only took off because "JavaScript everywhere" was taking off — performance be damned. Protobufs and other binary formats already existed, but JSON was appealing because it's easily inspectable (it's plaintext) and easy to use — `JSON.stringify` and `JSON.parse` were already there.

We eventually said, "what if we made databases based on JSON" and then came MongoDB. Worse performance than a relational database, but who cares! It's JSON! People have mostly moved away from document databases, but that's because they realized it was a bad idea for the majority of usecases.

The fact that you bring up protobufs as the primary replacement for JSON speaks volumes. It's like you're worried about a problem that only exists in your own head.

>wasting cycles to manifest structured data in an unstructured textual format

JSON IS a structured textual format you dofus. What you're complaining about is that the message defines its own schema.

>has massive overhead on the source and destination sides

The people that care about the overhead use MessagePack or CBOR instead.

I personally hope that I will never have to touch anything based on protobufs in my entire life. Protobuf is a garbage format that fails at the basics. You need the schema one way or another, so why isn't there a way to negotiate the schema at runtime in protobuf? Easily half or more of the questionable design decisions in protobuffers would go away if the client retrieved the schema at runtime. The compiler based workflow in Protobuf doesn't buy you a significant amount of performance in the average JS or JVM based webserver since you're copying from a JS object or POJO to a native protobuf message anyway. It's inviting an absurd amount of pain for essentially zero to no benefits. What I'm seeing here is a motte-bailey justification for making the world a worse place. The motte being the argument that text based formats are computationally wasteful, which is easily defended. The bailey being the implicit argument that hard coding the schema the way protobuf does is the only way to implement a binary format.

Note that I'm not arguing particularly in favor of MessagePack here or even against protobuf as it exists on the wire. If anything, I'm arguing the opposite. You could have the benefits of JSON and protobuf in one. A solution so good that it makes everything else obsolete.