--incremental Build, only process files that have changed.

[zachleat]

This is the step that requires knowledge of each template’s dependencies:

• What collections the changed template is a part of and what other templates consume those collections.
• Keep in mind JavaScript dependencies (for 11ty.js)
• If the file is a layout, rebuild other templates use the layout.
• If the file is a data file, rebuild what templates use the data (global data will require some extra work but directory and template data are straightforward)
  • Stretch goal here for huge pagination templates is that it would be super nice to know what changed in the data file to have a bit more precision about what pagination templates we need to write. (Selfishly I want this for my twitter archive project) (Filed separately at Incremental Builds stretch goal: incremental pagination data sets #1087)
• Passthrough copy files filed separately as Incremental passthrough copy #977

Punt into separate issues, later:

• If the file is a config file, package.json, rebuild everything for now.
• If the file is an include or an extend or an import or other internal-to-template-language specific feature, how do we discover what other files consume this? Maybe no way to tell for relative includes that don’t live in the includes folder?

[zachleat]

The really difficult part about this task is that doing it correctly would require a detailed dependency map of the content, specifically around what uses what collections.

[dillonbheadley]

I believe the pug cli watch option does this. Even if included css file changes it only rebuilds templates that reference it.
It’s very smart. Not sure how it’s done tho.

[zachleat]

This repository is now using lodash style issue management for enhancements (see https://twitter.com/samselikoff/status/991395669016436736)

This means enhancement issues will now be closed instead of leaving them open. The enhancement backlog can be found here: https://github.com/11ty/eleventy/issues?utf8=%E2%9C%93&q=label%3Aneeds-votes+sort%3Areactions-%2B1-desc+

[zachleat]

Use Object.defineProperties to add getters to track dependencies between templates and data.

[zachleat]

Proxies and Sorted Directed Acyclic Graphs, y’all.

https://www.npmjs.com/package/toposort
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy

[zellwk]

Just adding another thought: I wonder how would incremental watch mode work with a task runner like Gulp and browser sync?

[jakearchibald]

If/when this happens, it'd be great if the optimisations were available outside of watch mode.

TypeScript does this via .tsbuildinfo files.

This means that users that are using different watchers would benefit from the incremental build too.

[Ryuno-Ki]

Hm, some people referred different existing implementations. Could we gather their source code here so to lay out a plan?
(If we get lucky, we find shared libraries among them!)

[zachleat]

Did a really dumb/rough start of this here 6e294bd