Web + Android · 2025
From the jacket flap
Bookisham is a members' library that never hands over a file. Readers sign in on any device and read page by page from a canvas; an admin runs the shelf, the readers and the purchases. One Next.js server, two front doors: an installable web app and a native Android app.
Frontispiece
Particulars of this edition
The book in figures
Chapter I · Overview
Most reading apps hand the reader a file and hope for the best. Bookisham keeps the file: every book is paginated on upload, stored encrypted, and served one rendered page at a time through a session that belongs to exactly one device.
Readers create their own account, browse the shelf with prices and discounts up front, pay by UPI and attach the screenshot; an admin approves the request by eye and the book appears on the reader's shelf with a notification. The page they stop on is saved as they go, so a reload, or another device, lands on the same line.
The web app installs as a PWA and the Android app is native Kotlin with Jetpack Compose. Both speak to the same JSON routes, share the same one-device rule, and paint pages the same way: unwrapped in memory, drawn, and dropped.
The house rules
Pages are rendered on the server and painted onto a canvas. There is no file, no image URL and no text in the DOM.
A login ends every other session for that account. Sessions last 48 hours, whether or not the reader is active.
Selection, copy, print and dev-tools shortcuts are swallowed; the page is covered when the window is not in front.
Prices and discounts per book, a QR to pay, a screenshot as proof, and an admin decision that notifies the reader.
Books, covers and rendered pages are AES-256-GCM encrypted in the app before they reach S3. A public bucket would leak ciphertext.
A tagged push builds and signs the APK; the app checks the release feed, downloads inside the app and hands off to the installer.
Chapter II · Two front doors
In the browser · Next.js 15
Server-rendered pages on warm paper, with a service worker that keeps the shell offline-ready and stays away from anything that carries a page of a book.
The server renders its pages for the browser and exposes the same shapes as JSON for the phone. Whichever door a reader walks through, the shelf, the progress and the rules are identical.
On the phone · Kotlin
Shown here: the web app installed on a phone. The Android app mirrors every screen in Jetpack Compose with no third-party UI library, and adds what only a native app can.
* Shared by both: POST /api/auth/login · GET /api/me · GET /api/library · GET /api/browse · GET /api/books/:id · GET /api/read/:book/:page · POST /api/progress · POST /api/purchase-requests · GET /api/notifications · /api/admin/* · bk_session cookie · 48 h · one device per account.
Chapter III · Under the hood
Upload, read, protect. Each is a small chain of steps, and each ends with the same outcome: the reader sees the page and nobody holds the file.
In 3 parts
Pull a ribbon on the facing page to open its part.
Part the First
* Pieces: mupdf · mammoth · sharp · AES-256-GCM · @aws-sdk/client-s3 · Neon Postgres · schema applied on first boot · stateless with S3.
Part the Second
* Details: canvas only · ImageBitmap cache · page scrubber · fit-to-width zoom · keyboard paging · no service worker on /read · Cache-Control: no-store.
Part the Third
* Honest limits: Permissions-Policy: display-capture=() · no-store everywhere · ⚠ cannot stop a camera · ⚠ cannot stop a rooted phone · deterrent, not a guarantee.
Chapter IV · Key screens
One photograph, edge to edge, and the two things a visitor came for: how to reach us and where to sign in. The shelf is listed for everyone, with prices, so a visitor knows what is inside before creating an account.
A reader sees only the books they have been given, each with an ember progress bar and the page they are on. An admin sees every book, which is how they check what a reader will see.
A near-black surface so a white page does not glare in a dark room, one floating bar with zoom and a page scrubber, and a column of pages painted from bitmaps that never touch the disk.
The moment the window loses focus, the tab is hidden, the developer tools open or PrintScreen is pressed, the pages disappear behind a cover. Come back and they return where they were.
Everyone with an account, when they were last seen and how many books they hold. A new reader's password is shown exactly once; from a reader's page the admin ticks books, resets the password, signs a device out or disables the account.
Upload a PDF, EPUB or Word file with a cover, a price and a discount; edit or replace it later. Purchase requests arrive with the reader's UPI screenshot and are approved or rejected by eye, which grants the book and notifies the reader.
Chapter V · In the pocket
The web app on a phone: the same paper, the same shelf, the same reader. The native Android app follows these screens one for one.
Chapter VI · Threat model and stack
Next.js 15React 18TypeScriptTailwind CSSPostgres on NeonpgS3 · @aws-sdkMuPDFmammothsharpWeb CryptoService workerKotlinJetpack ComposeMaterial 3OkHttpkotlinx.serializationNavigation ComposeWorkManagerGitHub Actions
Chapter VII · More screens
Colophon
Bookisham: Private Reading Room, a private reading room, on the web and on Android.
Designed and built by one hand: Design · Full-stack · Android.
Shelved under Full-stack, September 2025. Status: Live.
Set in Next.js 15, Kotlin · Compose, Postgres, S3 · AES-GCM and PWA.
This page is typeset in Cormorant Garamond and EB Garamond, on paper the colour of an old library card.
Your guide through these pages: Bocchi, of Bocchi the Rock!.
Finis