Honzo

The "ideal" ebook format.

Honzo is a binary ebook format designed for simplicity, performance, and portability.

Features

Quick Start

Rust

use honzo_std::{HonzoParser, HonzoStream, Builder};

// Zero-copy parse
let data = std::fs::read("book.hzo").unwrap();
let p = HonzoParser::new(&data, 1).unwrap();
println!("{} chunks", p.head().chunk_count);
for entry in p.toc_entries() {
    println!("  {} - {:?}", entry.chunk_id, std::str::from_utf8(&entry.chunk_type));
}

// Streaming read
let file = std::fs::File::open("book.hzo").unwrap();
let mut stream = HonzoStream::open(file, 1).unwrap();
for chapter in stream.chapters() {
    let text = chapter.unwrap();
    println!("Chapter: {} bytes", text.len());
}

// Build
let hzo = Builder::new()
    .add_chunk(*b"CHAP", b"Hello, world!", Compression::None,
               MarkupType::Markdown, CoverType::Front, None, None, None)
    .finalize()
    .unwrap();

TypeScript

import { createReader, buildHonzo } from '@nisoku/honzo';

const response = await fetch('book.hzo');
const buf = new Uint8Array(await response.arrayBuffer());
const reader = await createReader(buf);
console.log(reader.chunkCount, reader.layoutMode);

const meta = reader.getMeta();
console.log(meta.title?.en);

C

#include "honzo.h"

HonzoHandle* handle = HonzoHandle_parse(data, data_len, 1);
uint32_t count = HonzoHandle_chunk_count(handle);

Repository Layout

Honzo/
  Cargo.toml                # Rust workspace root
  Build/
    crates/
      honzo-core/           # no_std wire-format + parser
      honzo-chunks/         # chunk semantics (SIDX, COVT, extras)
      honzo-io/             # builder/reader/stream + compression (std)
      honzo-convert/        # epub/mobi/pdf import
      honzo-c/              # C FFI bindings (Diplomat)
      honzo-wasm/           # wasm-pack target
      honzo-cli/            # CLI binary
    adapters/typescript/    # npm @nisoku/honzo
  Demo/                     # Vite web demo
  Docs/                     # Documentation site
  Tests/
    fixtures/                # Sample .hzo files
    corpus/                 # Edge case files
    tests/                  # Rust integration tests
  honzo.ksy                 # Kaitai Struct spec

Documentation

• Getting Started
• Format Specification
• API Reference

Contributing

See CONTRIBUTING.md.

License

Apache License 2.0. See LICENSE.