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by taeric 1081 days ago
Oddly, knowing the limitations of last year's designs can, as often, limit you to last year's solutions. That is to say, the reason things were done in the past almost always come down to resourcing constraints.

Yes, it is good to understand constraints. It is also incredibly valuable to be respectful of the constraints that folks were working on before you got there. Even better to be mindful of the constraints you are working on today, as well. With an eye for constraints coming down the line.

But, evidence is absurdly clear that large systems are grown far more effectively than they are designed. My witticism in the past that none of the large companies were built with the architectures that we seem to claim are required for growth and success. Worse, many of them were actively done with derision for "best practices" coming from larger companies. Consider, do you know all of the design choices and reasons behind such things as the old Java GlassFish server?

Even more amusing, is to watch the slow tread of JSON down the path that was already covered by XML. In particular the attempts at schemas and namespaces.

2 comments

> large systems are grown far more effectively than they are designed

It's easy to bake in poorly scaling technical decisions at an early stage that take an obscene amount of engineering effort to undo once the scaling problem become obvious. I've seen intern-days of "savings" turn into senior-years of rework and the scale in my corner of the world is tiny by SV standards.

I always assumed that SV companies experienced similar traumatic misadventures, multiplied up by scale, and baked "thinking at scale" into their technical interviews as a crude (but probably somewhat effective) countermeasure. Even if you only ever use the knowledge one time, indirectly and accidentally, by peer-pressuring your buddy into thinking before coding and therefore avoid a $10M landmine, it was all worthwhile.

It is as easy to bake in large maintenance and runtime costs on early stage development. Worse, it is easy to bake in aspirational growth ideas in the architecture that make it difficult to adjust as you go.

Is akin to thinking you need a large truck, when a very cheap pickup will do. Will the pickup scale to larger jobs you may grow to take on? Of course not. But it will be far cheaper to operate and own at the start, so that you can spare resources to get there.

Now, oddly, this can be taken in several directions. ORM is the poster child that folks love to hate on for how rigid it can be in a mid sized project. And it is also the poster child for how rapidly you can get moving with a database. Which is more important for a project? Really really hard to say, all told.

In contrast, there are a lot of systems out there designed to scale up really quickly, but never achieve the product-market fit to ever need this.

All that engineering for scalability would have been better applied toward things to find the right product-market fit.

It’s hard to strike the right balance of engineering in all aspects of a product. But I’d rather be at a company forced to pour hours of senior engineering effort into fixing scalability than one where things can scale to hundreds of millions of users, but you never attract more than a few thousand.

If they know the code base well, it shouldn't be that hard to undo intern-level shortcuts.

There's another failing here which is that quality wasn't gated well enough.

Hmm. This view works except where it doesn't. For example, if you don't pick the right ID/account/object # scheme so you can shard later on, good luck figuring how to distribute and/or scale the issuing of said IDs years down the road. Some things will never need to be sharded. Some things will kill you if you can't. Every bit of your code is going to make assumptions about this and you're maybe going to end up with a hot key that's hard to fix or have to do weird contortions to split your infrastructure by country or region where there are laws or regulations about data residency.

Here's a few others without explanation of how they'll blow up on you: not being careful about the process around managing feature flags, doing all your testing manually, not doing system level design reviews including the outline of a scaling plan for the system as planned prior to building systems, not building and testing every check in, doing system releases when it seems good or by marketing requirements instead of on a regular cadence, not having dev/test/production built via IAAC or at least by scripts that work in all envs. Not having runbooks.

>This view works except where it doesn't.

It only stops working in the worst case scenario though: LOTS of hastily written code (by interns?) that suddenly needs to scale and will take senior-level people years to do it.

If given that situation, most folks here would run the other way. That's years of toil for little career payoff, and a company in this situation is unlikely to be willing to pay for the best people to do it since they didn't want to pay for that in the first place.

It's very likely something like this will just die or get rewritten and it's probably for the best.

But some things are obvious once you build up scar tissue from previous experience.

And scaling could mean “it might work on a developers PC with 50 rows of data. But it won’t work with our current production load because he didn’t index a table”.

To me this is a entirely separate problem.

I’ve noticed that when less experienced people try to solve a problem, they have to look up how other people do it first.

But someone more experienced has a strong understanding of technologies on an abstract level so they can whiteboard a solution without even involving any specific software (then compare to how others do it). When you think that way, you’re not worrying about JSON or XML. You become neither tied to last year’s tech or too eager to try new tech. You just build something solid that’s reliable and long-lasting.

Knowing about different tech used in different designs expands the pool of legos that you can snap together and so it can’t hurt.

There is a similar learning style. Basically, guess the answer and then compare to the other answers. Even before you know anything about it, all told.

That said, I have as often fallen into the trap of trying to build it myself first. So called "first principals" thinking. That works far less often than folks think it does.