Stop 08 · Technical Fluency for PMsTopics · 10/11

Reading a Technical Spec

In short

Engineers write design docs before big builds. You don't approve the code choices, but you're the best person to spot where the plan quietly drifts from what users need.

Engineering design docs describing how a system will be built — a PM doesn't need to approve every technical detail, but should be able to spot when the approach doesn't match the product goal.

The purple blob reads a long paper estimate while a mechanic points at a car's open bonnet.

Think of it like this

The mechanic's estimate

The mechanic hands you a long estimate full of part names. You can't judge the gaskets. But you can check: is the AC fix included, which was the reason you came? Is that extra polish charge something you asked for?

Watch it happen

Where a PM should focus in a design doc

Design doc

Context & goals

Non-goals

Proposed design

Alternatives

Risks & rollout

1/5Goals: does the doc describe the same user problem and success metric as your PRD?

The big ideas

What you need to know

Check goals match

Your biggest value is catching a mismatch between the spec's goals and the user problem.

Look for user impact

Translate technical choices into what users will see, wait for or lose.

Ask, don't approve

Leave questions as comments. Technical choices belong to the engineers.

Read it early

Comment while it's a draft. Changing the plan after build starts is expensive.

Save yourself the pain

Common mistakes

Oops

Skipping the doc because "it's technical".

Do this instead

Read the goals, non-goals and rollout sections at least. Those are written for you too.

Oops

Debating the choice of database in comments.

Do this instead

Focus on user impact, scope and risk. Trust engineers on internal choices.

Your mission

Review a public design doc

~30 min

Quick check

Which comment is most useful from a PM on an engineering design doc?

Go deeper

1Read a public engineering design doc from a company's engineering blog.
2Practice identifying the parts relevant to product scope vs pure implementation detail.
3Ask clarifying questions instead of nodding along when something is unclear.