---
title: Zero cost optimizations
date: 2021-04-03
description: Some optimizations come at virtually no cost. This can be in any area of life, not just in programming. Even if their benefit is limited, the cost is practically zero. So why not do them?
---

Some optimizations come at virtually no cost. This can be in any area of life,
not just in programming. Even if their benefit is limited, the cost is
practically zero. So why not do them?

In this post I want to share some thoughts about the structure of this kind
of optimization.

## Examples

That sounds very abstract, so what do I mean by this?

One example would be accessibility. As a frontend developer you should know how
to create accessible websites. I am not talking about the
full-on-works-better-with-a-screenreader kind but just something that avoids
the most common pitfalls. If you already know how to do it, why not do it all
the time? It may not be a hard requirement in every project, but it sure is
better than not doing it.

Another example is code styling. If there are agreed upon norms for writing
code in a specific language, why not just use them?

One example from another area of life would be veganism. For the largest part
it is healthier, kinder, and more sustainable than eating meat. There is no
extra effort involved. I see no reason against it.

## Counter arguments

Obviously not all people value accessibility, code styling and veganism. I want
to look at some common counter arguments:

### You ain't gonna need it

[YAGNI](http://c2.com/xp/YouArentGonnaNeedIt.html) is a reminder against
feature creep. Even if you think you will need a feature, don't implement it
until you *actually* need it. I think this is valuable advice in many
situations. However, all examples I mentioned were about doing a thing
*differently* rather than adding something new on top. So I don't think it
applies.

### Effective altruism

[Effective
altruism](https://www.jefftk.com/p/effective-altruism-and-everyday-decisions)
is a movement focussing on the optimizations with the highest impact. Their
position is that you should not waste time and energy on low-impact
optimizations if there are more effective things you could do instead.

This, again, is a very good point. The examples I mentioned all have high
efficiency (high impact/cost ratio) but low effectiveness (low total impact).
Still, I see no reason not to do them. I would rephrase this critizism as:
"Don't spend time arguing about it, just do it". (I am aware of the irony of me
writing a blog post about this topic. We all have our faults.)

### Virtue signalling

[Virtue signalling](https://www.urbandictionary.com/define.php?term=Virtue%20Signalling)
is the allegation that people do zero cost optimizations not for their benefits
but to show off.

This argument can be reversed easily: People who do *not* do these little
optimizations obviously just do it to show that they do not care. If you talk
to someone about climate change and they order a steak, that is a statement.

Sure, I guess all these are signals. But that is mostly because ["one cannot
not communicate"](https://en.wikipedia.org/wiki/Paul_Watzlawick). I would argue
that this form of communication is even useful in most cases. It is good to
know whether the person I talk to actually knows and cares about the topic.

## Habits and teams

When I say these optimizations come at zero cost, that is only true for the
long term. When you are just starting you may need to change your habits, and
changing habits is hard.

If you work with others you usually need to align your habits and expectations
to a certain degree. If you only eat vegan food you will force this on anyone
who invites you to dinner. The same is true if you insist on a specific code
style during code review.

As you usually communicate with different people, you need to have some degree
of flexibility in your habits. If you over-optimize, you will have a hard time
fitting in.

## Conclusion

Zero cost optimizations, also called "virtue signalling", are efficient but
ineffective actions based on habits. Arguing about them is not worth the time.
But doing them totally is.