[salman89]

I agree with the general premise of avoiding premature optimizations, but designing systems that scale is important for several reasons:

- Startups grow exponentially, if you're playing catchup as you're growing you are focusing on keeping the lights on and hanging on for the ride. Important for a growing company to focus on vision.

- Software that scales in traffic is easier to scale in engineering effort. For example, harder for a 100 engineers to work on a single monolith vs 10 services.

- Service infrastructure cost is high on the list of cash burn. Scalable systems are efficient, allow startups to live longer.

- If the product you are selling directly correlates to computing power, important to make sure you are selling something that can be done profitably. For example, if you are selling video processing as a service, you absolutely need to validate that you can do this at scale in a profitable manner.

I also don't agree with the premise that speed of development and scalable systems are always in contention. After a certain point, scalable systems go hand and hand with your ability to execute quickly.

[Michielvv]

In the projects that I was involved in in the past years, the ones that decided to build a scalable infrastructure before gaining traction were exactly those that were burning cash on infrastructure. There is just a reasonable minimum of servers you need to run such an infrastructure and then you need something similar as a staging environment to make sure it all works together correctly.

That being said, there are of course choices that can be made early on that will help you in case you need to scale at some time. Spending a bit of time thinking through what would happen if you do need to split up and scale out your system will help you avoid pitfalls such as relying too much on the local filesystem being shared across pageviews.

In general I believe there is more benefit on spending time on performance early on. (not caching, that is just postponing the problem) as it benefits not just your ability to run on a single system for much longer, it will also make life better for your users.

[salman89]

Scalable system does not imply needing many machines. There is no reason you can't just deploy your entire system on a single host, but maintain the ability to reconfigure exactly when needed.

But yes - its about finding the right balance.

[mk89]

I totally agree with you on all the points.

I think it takes experienced managers and developers with business-oriented mindset to achieve the best compromise. Saying "there is no need to overengineer now" can be as bad as months of overengineering. It all depends on the business.