Strunkifying Whitener
Strunkifying Whitener marks your Markdown drafts with rule numbers from the 1918 private printing of The Elements of Style, the way Strunk marked his students’ manuscripts. A red 13 in the margin means “omit needless words” probably applies to that line. It never rewrites your prose, never suggests a replacement, and never gives you a score.
You keep writing in your own editor. In Chrome or Edge, it follows the file and re-marks it every time you save, and the paragraph you just changed becomes the current one.
One tier at a time
The rules come in tiers, in the book’s order: usage first (rules 1 to 5 and the commonly misused words), then composition, then the rules that need judgment. A paragraph with a comma splice shows only that. Once you fix it or dismiss it, the next tier’s marks appear. Paragraphs move through the tiers independently, so a stray comma in the first paragraph doesn’t hide anything in the fifth.
The judgment rules, like “use definite, specific, concrete language,” don’t get marks. They become question cards, on request, for the current paragraph: Strunk’s full text for the rule, your own notes on it, and the questions a careful writer would ask.
Any mark can be dismissed. Strunk allowed that good writers break rules when the sentence gains something in return. A dismissal shows as “stet” in the margin and lasts until you edit that sentence.
The look
The marks are drawn as fountain-pen ink in red and blue, with proofreader’s carets for missing commas and rule numbers in a handwriting face. A print view double-spaces the draft with the margin marks, for revising at the typewriter.
The whole thing is one HTML file with no build step and no libraries. Your text stays in your browser unless you ask a model of your own choosing for a second opinion.