Unity Performance Tuning Bible: a Re:VIEW book you build, translate with DeepL and read for free

A book whose source is the deliverable

The repository is not a Unity package and not a tool. It is the source of a book about Unity performance tuning, and the fact that the sources are public rather than the finished artefact is the interesting part of the design.

The content lives in an articles/ directory in Re:VIEW format. Everything downstream is generated from it. The build scripts in package.json name the targets explicitly:

"pdf": "grunt pdf",
"md": "grunt markdown",
"html": "grunt html",
"text": "grunt text",
"epub": "grunt epub",
"idgxml": "grunt idgxmlmaker",
"vivliostyle": "grunt vivliostyle",
"web": "bash build-web.sh"

PDF, Markdown, HTML, plain text, EPUB, IDGXML and a Vivliostyle render are all separate outputs from the same chapters, and there is a dedicated shell script for the web edition. The test script is npm run html, so the HTML build is also the correctness check.

The build stack is old and deliberate. Grunt 1.6.1 with grunt-cli is still the task runner, load-grunt-tasks auto-loads the plugins, and there are overrides pinning minimatch, brace-expansion and ansi-regex to specific versions. Node 16 is the declared floor. A.ruby-version file and a Gemfile sit alongside because Re:VIEW itself is Ruby, and the postinstall script runs bundle install so a fresh checkout gets the Ruby side automatically.

Other root files explain themselves by name: build-search-index.js generates search data for the web edition, rebuild-css.sh handles styling, redpen-conf-ja.xml is a proofreading rule set for Japanese, and prh-rules/ holds the rule files it points at. Third Party Notices.md is present, which is what a book that embeds third-party content needs.

Building the PDF needs TeX Live with Japanese support

Reproducing the PDF outside GitHub means reproducing a fairly large toolchain. The repository ships a Dockerfile that installs it, and the entry scripts build-in-docker.sh and build-in-docker-epub.sh are there so you do not have to install any of it locally.

The base image is Ruby, and the package list includes several TeX Live components for Japanese typesetting:

FROM ruby:3.3-bookworm

# TeX Live + Japanese support for Re:VIEW PDF builds
RUN apt-get update && apt-get install -y --no-install-recommends \
    texlive-luatex \
    texlive-lang-japanese \
    texlive-lang-cjk \
    texlive-fonts-recommended \
    texlive-fonts-extra \
    texlive-latex-recommended \
    texlive-latex-extra \
    texlive-plain-generic \
    texlive-extra-utils \
    lmodern \
    pandoc \
    nodejs \
    npm \
    ghostscript \
    && rm -rf /var/lib/apt/lists/*

RUN gem install bundler:4.0.3

Node and npm are present because the Grunt tasks run inside the same image. The Ruby side pins bundler to 4.0.3 explicitly rather than relying on the image's version.

The work directory inside the image is /book.

If you want the finished artefact rather than the pipeline, there is a much shorter path. The README documents downloading an ebook PDF from the Assets section of the latest GitHub release, and separately links a hosted web edition. Reading requires no build at all.

No licence is applied, and copyright still applies

This is the section most people skim and most people should not.

The README states, in its licensing section, that no licence is applied to this repository while copyright law does apply, and it links to GitHub's documentation page on choosing the right licence for a repository. The repository's licence metadata is correspondingly empty.

That combination has a precise meaning and it is not permissive. Without a licence grant, the repository provides no general permission to copy, modify or redistribute the work beyond what applicable law permits. A copyright notice reserves rights; it does not grant them. So you can read the book, and the README invites issues and pull requests, but the permissions a reader would assume from a repository with an open source licence are not granted here.

The copyright line reads (C) 2022 CyberAgent, Inc.

This matters most for the translation workflow described below, because that workflow asks individuals to produce and distribute translated PDFs. The maintainers took a deliberate position on it, and they took it by documenting a process rather than by attaching a licence. Anyone producing a translated edition should read the licensing guidance the README links to and, if the intent is distribution rather than personal use, settle the question with the rights holder rather than inferring permission from the existence of a translation guide.

Translations are delegated, and DeepL does the work

Translation requests arrived as issues, and the maintainers decided that releasing official translations was operationally unworkable, so they handed the work to individuals. That is the stated reason, not a stylistic preference.

Alongside that decision they tested whether an automated translation service could produce acceptable editions, and report that translating the original Re:VIEW format with DeepL made it possible to provide editions and keep providing them going forward. A translation/ directory in the repository holds the instructions, and the mechanism is a language parameter: change it and you get the translated PDF for the language you want.

Two constraints are stated. Official releases support English only, and other languages are left to individuals following the flow in the translation README. And the caveat is explicit: translation quality depends on DeepL, and the pipeline is offered on the premise that it is somewhat easier than translating by hand, not that it is as good.

Updates to translated editions follow a stated policy: typos are out of scope, and updates happen on major changes or additions rather than continuously. In other words a translation tracks the original loosely, and a reader of a translated edition should assume they may be reading a slightly older chapter set.

The Documentation/ directory and the two README files, one Japanese and one English, mean the web edition is served in both languages. The English README is a translation of the original rather than the original itself, which is a detail worth holding onto when judging accuracy.

What the repository says about the content, and what it does not

The README describes the book as a systematic compilation of Unity performance tuning know-how, and that description is the entire statement of scope. There is no table of contents in the README, no chapter list, no Unity version range, and no statement of which platforms or render pipelines the advice applies to.

That absence is worth being explicit about, because it changes how you should treat the material. This is not a checklist you can apply mechanically to a project. The repository tells you it is a book, and everything else requires opening it. The Documentation/ directory is where the web edition assets live and the logo is at Documentation/bible_logo.png, but the README gives no page-per-chapter breakdown.

There is also a pull request badge inviting contributions, which is the one signal about how open the project is to change. Given that the same repository states no licence is applied, an incoming pull request is handled under whatever arrangement the maintainers agree, which is a process you would need to raise rather than assume.

The honest summary is that this is a professional reference published as an open repository of sources, with the practical benefit being that you can read it in the browser, download a PDF, or run the pipeline yourself to produce a translated edition. It is not software, it has no runtime behaviour to evaluate, and its usefulness depends entirely on whether the advice matches the Unity version and project you are working on.

Editorial conclusion

Adopt Unity Performance Tuning Bible as a reference and, if your team works in Japanese, as a template for producing a translated edition, since the translation pipeline is documented and reproducible. Do not treat it as free software you can fork: the README states that no licence is applied to the repository while copyright law still governs it, so read the licensing page GitHub links before reusing any text. Verify first which edition you are reading, since the English web version, the DeepL-translated PDFs and the original all describe the same chapters at different translation quality, and the maintainers themselves caution that translation quality depends on DeepL.

Frequently asked questions

Official sources

1. CyberAgentGameEntertainment/UnityPerformanceTuningBible on GitHub
2. Issues
3. README
4. Releases