You’ve been there. You spend a week mapping out every edge case, formatting the headers perfectly, and detailing the architecture. You drop the 15-page design doc in Slack. An hour later, the senior engineer replies with three words: “Looks good to me.”
That’s not a review. That’s a dismissal.
We treat design docs like historical records, trying to capture every detail in case someone five years from now needs to know why we chose Redis over Memcached. But the truth is, nobody is reading your design doc for fun. They are reading it to make a decision.
Silence from your reviewers isn’t a documentation flaw—it’s a social failure.
If nobody is arguing in the comments of your design doc, you haven’t written a design doc. You’ve written a eulogy for a project that will inevitably derail.
The problem isn’t that you lack detail. The problem is that you are writing a process artifact instead of a persuasive memo aimed at specific decision-makers. At massive companies like Google and Microsoft, design docs thrive because they are treated as weapons of alignment, not bureaucratic checklists. At a 50-person startup, a 15-page formal doc is overkill; a one-pager that forces a decision is all you need.
A design doc isn’t an encyclopedia of your codebase; it’s a weapon to force alignment before a single line is written.
Think about the vulnerability of writing one. You are putting your technical judgment on the line. You are saying, “I think we should build it this way, and here are the risks.” If you bury that judgment under pages of API schemas and sequence diagrams, you are hiding behind process. You are avoiding the conflict that makes architecture good.
Stop trying to be exhaustive. Start trying to be persuasive. Who needs to approve this? What trade-offs are they going to care about? Scope the doc to the decision it needs to enable. If you’re building aerospace software under DO-178C, yes, you need exhaustive compliance documentation. But for 99% of us, we just need to get three busy engineers to agree on a database schema.
If your design doc doesn’t make at least one person uncomfortable, you haven’t surfaced the real trade-offs.
Write from the reader, not at them. Bring them the tension before you bring them the solution. Involve the right people before the draft even exists. Because the worst time to discover that your lead architect disagrees with your core approach is after you’ve already written the code.
Your design doc is not a deliverable. It is the crucible where good engineering is forged. Make them read it. Make them argue. Make it count.
FAQ
Q: What if my team actually needs exhaustive documentation for compliance?
A: If you're building aerospace or medical software under strict regulations like DO-178C, you need exhaustive specs. But don't confuse compliance documentation with a design doc. A design doc is for aligning decision-makers; compliance docs are for proving you did the work.
Q: How do I get busy engineers to actually read my doc?
A: Stop writing encyclopedias. Scope the doc to the specific decision you need them to make. Put the controversial trade-offs on page one. If you make it easy to argue with you, they will read it.
Q: Isn't it risky to write a doc that provokes disagreement?
A: The only real risk is writing code based on an assumption nobody agreed with. A design doc that sparks a fierce debate has done its job. A doc that gets a silent "LGTM" is a ticking time bomb.