🏁 Roadmap & Iteration plan Q2-Q3 2023

[bigopon]

A roadmap and an iteration plan will be provided & updated below for better clarity on the focus of the development

🗺️ Roadmap

Main featrures

• @children and <au-slot> #1205
  This is a missing feature for application migrating from v1. Even though via some hacks, the current @children can provide the desired outcome, but it's not appropriate. A new decorator @slotted is needed as equivalence of @children for <au-slot/>
• getter/setter for @bindable #1602 #1180
  This is necessary for preparing for the incoming official decorator feature of the JS language. As it'll be common for people to use @bindable on getters/setters & auto accessors
• global identifiers in our template #1490
  This is commonly needed in all applications. As apps grow it'll be just boilerplate for some global values since they are used everywhere. This also helps make our template more natural and close to standard JS
• SSR implementation preparation #1698
  This is a crucial feature for many of our users as it enables many high level development frameworks on top of Aurelia, as well as unblock use cases for our users applications. This also helps us assert how far we are from static site generator (SSG)
• partially pre-compile template (~partial AOT) #1504
  Precompiling our template & binding expressions during build time could help further reduce application startup time, and gives better startup performance. While the end goal is the ability to automatically recognize all code and collect the resources, we can start with simple manual config/json file to help the pre-compiler achieve this output so applications can start benefiting.
• Vite plugin: this is a commonly requested feature, as well as a good to have item, since the development experience with Vite is nice. The main work was done awhile ago but the actual plugin still needs to be released. #1651

Other fixes & improvement

• Upgrade TS version to 5.0, there may or may not be a lot of issues. We probably can clean up quite a bit our code base too. TS is also smaller and faster, so it should help with development speed a bit. #1711
• Cleanup & optimize the routers. The routers at the moment don't make efforts to save on size, or DX, it should be improved with our __DEV__ setting. #1712
• resolve inconsistency between local template & convention #1091
• investigate a way to flush debounce & throttle on signal #1145
• add support for property injection #1742
• add support for getter based observer location #1747
• simplify resources system #1749
• auto inferred binding expression #1259
• @newInstanceOf and @newInstanceForScope work with interface #1765
• stop using au class to mark rendering targets.
• <au-compose/> pass through props (#497) + containerless support

📍 Iteration plan

• April: upgrade TS to v5.0 so a new foundation can be established. Since TS is a dev dependency and there' not a lot of breaking changes, maybe our tooling won't break/or too badly.
• April: Support global identifier in AST & the ability to retrieve children of au slot are useful and necessary for applications so they should be implemented first, as they are not big in scope.
• April/May: implement the @slotted behavior
• April - June: First part of SSR. It'll start by investigating a separate rendering mode hydrate, in which the hydrator knows how to distribute a DOM structure to each instruction for a definition. This is like the testing ground for SSR output. After this step, we can execute the server side part of SSR
• April - Aug: The work on pre-compilation of template can start in parallel, as it's more tooling focused, and thus has more freedom and less shared areas with other work. We'll need to start with some basic assumption like known global resources and make it more flexible eventually. @fkleuver probably can work on this.
• April: release Vite plugin

There could be some more bug fixes/small improvements made depends on the necessity.

✔️ Statuses

item	status	PRs
upgrade TS 5.0	✅	#1711
vite plugin	✅	#1726
@children, @slotted & <au-slot>	✅	#1735
flushable debounce/throttle	✅	#1739
property injection	✅	#1748
getter observer	✅	#1750
getter bindable	✅	#1753
newInstanceOf/forScope + interface	✅	#1767
stop using au class to mark rendering target	✅	#1768
global variables	✅	#1790
<au-compose> pass through + containerless	✅	#1792

🏁 Next steps

• virtual repeat #937
• optimize lifecycle to support arbitrary activation/deactivation
• upgrade decorators to be compatible with incoming official decorator feature. This will rely on the decorator metadata proposal https://github.com/tc39/proposal-decorator-metadata
• more to be updated

[swalters]

The roadmap is great and much appreciated. Can you add the planned timing for a production or LTS support release?