Introducing SEED.html

[seed_html]

Hi everyone,

As someone who's spent a lot of time thinking about and creating EPUBs, I know how tricky it can be to get the formatting just right and to ensure the final file is valid. I'm a software developer from Naarm/Melbourne, and I've created a new browser app that might make this process a lot easier for you.

The app is called SEED.html, and it's designed to help you quickly author clean, valid EPUB 3 books from simple Markdown or plain text files. It handles a lot of the technical grunt work for you, like generating a valid OPF file, creating a table of contents, and ensuring the final package is as close to valid as possible.

SEED.html has a minimalist, opinionated design that focuses on simplicity and speed. It's still very new and under active development, so I'm keen to get feedback from users to help shape its future.

You can use it on my web site, or download it to your own computer. It runs on all operating systems including iOS and Android though it's easier to use on a desktop.

https://stewarthaines.com/epub

I'd love for you to try it out and let me know what you think. Your feedback on the features, user experience, and any bugs you find would be incredibly helpful.

Thanks for your time,
Stewart

[seed_html]

There's a new easy way to create a valid EPUB 3 file.

I'm creating a browser-based app called SEED.html that lets you write in markdown and package as valid EPUB.

It's opinionated, and not bug-free, but it might be of interest to some here.

https://blog.stewarthaines.com/2025/...n-in-epub.html

[JSWolf]

Originally Posted by seed_html

There's a new easy way to create a valid EPUB 3 file.

I'm creating a browser-based app called SEED.html that lets you write in markdown and package as valid EPUB.

It's opinionated, and not bug-free, but it might be of interest to some here.

https://blog.stewarthaines.com/2025/...n-in-epub.html

To me, this looks more complicated to use then Sigil.

[Quoth]

Originally Posted by seed_html

There's a new easy way to create a valid EPUB 3 file.

I'm creating a browser-based app called SEED.html that lets you write in markdown and package as valid EPUB.

It's opinionated, and not bug-free, but it might be of interest to some here.

https://blog.stewarthaines.com/2025/...n-in-epub.html

There are markdown to "whatever" format converters already.

Almost no-one, and no fiction authors use markdown. Either LO Writer, Word or plain text.

Markdown on it's own isn't enough for textbooks.

Already Sigil & Calibre are mature products, better than InDesign, for reflowable epub. They can take a variety of inputs. Calibre and LO Writer can accept Markdown.

[Quoth]

Calibre & sigil do this better and for a lot more formats.

A browser app is madness.

[seed_html]

Hi Quoth, thanks for the feedback.

The browser app architecture is unusual, I will admit. But it means the app is available wherever there is a modern browser - including Android and iOS. The app can also be downloaded as a self-contained html file, so can be used offline.

I wonder if there are there things you'd like to be able to do within the EPUB 3 format that Sigil and Calibre don't support particularly well? That's the space that's interesting for me.

[Moonbase59]

Originally Posted by seed_html

There's a new easy way to create a valid EPUB 3 file.

Not so new, maybe. It’s just a Pandoc one-liner to create a finished, valid and astonishingly good-looking EPUB3 from Markdown, and I’ve been using it for far more than a decade now (EPUB2 at the beginning). If needed, extra polishing could be done using Sigil or the like. The same source files can even be used to produce a print-ready 5x8 or 6x9 PDF in a snap.

I personally know many editors that still prefer raw TXT or Markdown, and I know many novelists that prefer distraction-free working with software like Ghostwriter, Manuskript, NovelWriter and others. Concentrate on content, not a zillion clicky glitzy options. Or get lured into font and formatting options they would typically use the wrong way. They’re authors. Publishers shall do the work of publishing.

Many, if not most, authors do use Word or LO Writer, agreed. Everyone tells them to (not the best advice in my opinion), or they just like the easier workflow with their editors when it comes to corrections.

With the advent of self-publishing, we’ve seen a lot of rubbish appear, naturally. Crappy content, technically almost unusable EPUBs, but sadly also good content packaged in EPUBs done wrong. And of course textbooks and academic writing are an entirely different beast. With these, you’d also have to follow rather stringent publisher or university rules.

That said, why not have another option? Everything seems to go the "cloud" and "in the browser" way. It’s just some authors prefer to not get distracted (that’s so easy if online!), or write in places where they aren’t online.

[seed_html]

Originally Posted by Moonbase59

And of course textbooks and academic writing are an entirely different beast.

Hi Moonbase59,

I'm glad you brought up academic writing. There is a sample project which uses latexjs in the SEED.html app to create an EPUB from LaTeX formatted plain text. It looks like this;



The link below will open directly in the app, hosted on my domain, and load a sample epub with LaTeX content.

https://stewarthaines.com/epub/SEED....025-08-08.epub

To download the .epub, just click 'Package EPUB' button in the bottom left. Couldn't be easier!

[seed_html]

https://stewarthaines.com/epub/SEED....025-08-08.epub

That link should work.