Technical spec template
A design document should let a reviewer understand a change without a meeting: the context, the architecture, the limits and the open questions. This template has each section, a linked table of contents, and two Mermaid diagrams you can edit in place.
What each section is for
Context
The problem, in a paragraph a newcomer understands.
Architecture
One diagram of the parts and how data moves between them.
Limits
The numbers that bound the design, each with the reason behind it.
Open questions
What is not decided yet, so reviewers know where to push.
Questions
How do I edit the diagrams?
They are Mermaid code blocks: change the text and the diagram redraws. See Mermaid to PDF.
Does the table of contents update itself?
Yes. [TOC] lists the current ## and ### headings each time the document renders.
See also
Updated .