mastro

A minimal, no-dependencies take on an Astro-like MPA web framework.

Not production-ready, this is currently an experiment. I just wanted to see what the simplest web framework I could think of would look like that still offered a nice developer experience.

• No dependencies (except Deno's Standard Library).

• No magic. Easy to understand codebase using simple JS functions wherever possible. (That's why we're using JS functions to generate HTML instead of JSX or HTM.) Favour small, composable functions.

• File-based routing: routes/ contains files with handler functions and that's the only way. No .md files with layout frontmatter property, no .astro-like-frontmatter-magic, no .html files, etc.

• JSON and HTML route handlers are uniform. A handler takes a Request object (and no props, and hopefully no context).

• Components are simple JS functions that by convention take a props object.

How to run

To run the static site generator:

deno run --allow-read --allow-write --allow-net libs/generate.ts

TODOs

• Currently, Mastro only does static-site generation. Why start with SSG? And why focus on MPA? See my blog post. But the framework is designed so that we can implement server.ts easily (hopefully even supporting HTTP streaming), SSG is a special case of SSR with synthetic requests being generated at build time in generate.ts.

• Currently, doesn't support any interactive islands. I would have liked to add SolidJs-island support, but seems that would require babel or a similar transpiler. Perhaps Preact is a better fit, as seen in Deno Fresh. Ideally, we could do something like Qwik's resumability, perhaps using Maverick.js signals.

• Asset handling (CSS and images) – perhaps we should support something like CSS Modules and image resizing and do that on server startup / static site generation?

How small is it?

Excluding the basic blog contained in this repo, by counting the number of lines in the libs/ folder we have 160 lines of TypeScript (including comments). For reference, linecount can be calculated with the following nushell command:

ls libs/**/*.ts | select name | insert linecount { |file| open $file.name | lines | length } | math sum