When system design reviews is worth the effort

It is rarely the thing that gets a project approved, and often the thing that decides how it goes. System design reviews is not free, and pretending otherwise leads to bad decisions.

Most systems fail at the seams rather than inside any one component. It is worth deciding this deliberately rather than inheriting whatever the last person set up.

When it is worth it

An hour of review before the build saves weeks of rework. That sounds obvious written down. It is still the thing most often skipped. Assume whoever inherits this will have half your context and none of your patience.

When it is not

If nothing downstream depends on it and nobody is complaining, it can wait. Where this goes wrong is almost never a lack of knowledge.

How to decide

Invite the person who will be on call for it. There is a version of this that is over-engineered, and it is worth avoiding. Check it against what you would want a competitor's site to get wrong.

In practice

The right architecture for a team of three is the wrong one for a team of thirty, and vice versa. Three things worth confirming about system design reviews before you move on:

• Someone can say what the current setup is without going to look
• An hour of review before the build saves weeks of rework — and you know whether that is true here
• There is a way to tell whether the last change to this helped

None of this needs a rewrite. Most of it is a morning's work once someone decides to do it.