Ceejbot writes a "high-octane version" of their longer blog post on writing design docs. I like the phrase "high-octane version", I'm going to start using that.
They cover what to include, what it shouldn't and why to write it. If there's one take away, for me it's this:
The deliverable you care about you care about is shared understanding of a problem and alignment on a solution.
I discovered this write-up through Denis' week notes.
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