Getting started

npm install cupertino-files

That's the whole setup. No runtime dependencies, no native modules, no Apple software. It runs in Node 22 or later, and in the browser—bytes in, bytes out.

Open. Edit. Save.

import { readFileSync, writeFileSync } from "node:fs";
import { PagesDocument } from "cupertino-files";

const doc = PagesDocument.load(new Uint8Array(readFileSync("Report.pages")));

doc.bodyText;                                   // read it
doc.replaceText("2024", "2025");                // change it — styles survive
doc.appendParagraph("Conclusion", "Heading 1"); // styles by name
doc.setPageSetup({ topMargin: 72 });            // points

writeFileSync("Report 2025.pages", doc.save());

Use the typed loader when you know the app. When you don't, IWorkDocument.open(bytes) looks at the document and decides. Starting without a file at all also works: PagesDocument.blank() is a fresh A4 document, NumbersDocument.blank() a fresh spreadsheet, KeynoteDocument.blank() a fresh 16:9 deck.

Everything you leave alone is preserved, byte for byte—even in documents from app versions newer than this library.

Spreadsheets and slides

import { NumbersDocument, KeynoteDocument } from "cupertino-files";

// Numbers
const sheet = NumbersDocument.load(bytes);
const table = sheet.tables()[0]!;
table.setCell(0, 0, { type: "text", value: "John Appleseed" });
table.setCell(1, 0, { type: "text", value: "Anna Haro" });
table.setCell(0, 1, { type: "number", value: 42 });
sheet.addSheet({ name: "Forecast" });

// Keynote
const deck = KeynoteDocument.load(bytes);
deck.slides()[0]!.title = "Q3";
deck.slides()[0]!.notes = "Pause here. Let it land.";
deck.addSlide({ copyOf: 0 });
deck.addImage(1, pngBytes, { fileName: "chart.png" });

From here, the full tour covers text, styles, tables, fields, slides, and drawables; the capability matrix lists everything.

Some documents are politely declined

• Password-protected documents—refused; this library decrypts nothing (see legal posture).
• iWork ’09 XML documents—a different, older format; refused with a clear error.

When something can't be done, the error says why, and usually what to do instead.