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 and up, 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 });

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.