Design notes

The reasoning behind the decisions the usage documentation states as contract. Each page here answers why; the page it points back to answers what.

These notes are for whoever contributes to FuncToWeb, or is simply curious about why something is the way it is. Nothing here is needed in order to use the library.

• architecture.md — why the line between the public API and the merely visible internals falls where it does. → architecture.md
• files.md — why /upload does not apply the field limit, why a second upload of the same reference is a 409, and where custody of a promoted file ends up. → files.md
• frontend.md — why the content type is decided rather than guessed, why every icon is a file, and why the page adds almost no color of its own. → static-assets.md
• history-1.6-to-2.0.md — why 2.0 breaks what it breaks: the two layers underneath were rewritten, and what that widened, lost and left as a limit. → migration-1.6-to-2.0.md
• outputs.md — why table rows are read with itertuples(), why a matplotlib figure is closed, and why a union cannot mix a download with an ordinary branch. → outputs.md
• prefill.md — what happens between the prefill query parameter and the HTML that is served. → prefill.md
• router.md — why both storage TTLs default to one hour, and why the theme is resolved in pure CSS with no selector yet. → router.md
• run.md — why the space index navigates with location.replace() and carries no form logic of its own. → run.md
• sdk.md — why the modal does not close itself by default, why error is not about validation, and why the payload of result is the envelope of /invoke again. → sdk.md
• streaming.md — how print() capture works, why it is experimental, and why the transport polls. → streaming.md
• web-function.md — why the description is passed through cleandoc(), and why only the first letter of a displayed name is uppercased. → web-function.md

New entries go in this same flat list, one bullet per design document, in alphabetical order by file name: the file name as the link text, an em dash, one sentence saying what the page explains, and an arrow back to the usage page the reasoning came from. No sections and no grouping, so a page can be appended without restructuring anything.