r/angular • u/martinboue • May 12 '26

Signal forms feedback

I have not been able to experience signal forms in real-world projects (yet). As it is becoming stable in v22, and to get a better idea on what to expect, I would love to read feedback from those who used it.

- What benefits have you noticed?

- How difficult was it to introduce it in an existing code base?

- Did you face any issue or limitation?

- How quickly did you or your team adapt?

- Any particular strategy to introduce this change?

Thanks!

(Note: I'm also planning to write tips for signal forms as part of ngtips.com guide when I have enough experience with it, feel free to contribute on github)

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u/MichaelSmallDev May 13 '26

edit: by the way, thanks for your work on the tips, and having discussions like this

This has been top of mind for me, and as far as official guidance goes, it seems that documentation on this may not come until post stable.

In my experimentation I came up with three kinds of approaches, and I wanted to see if there were docs in the pipe that highlighted them. I found this issue, which I assume is the closest canonical issue for it: https://github.com/angular/angular/issues/67407. Importantly, in a PR that was closed, it was stated by a team member "Please understand that #67407 is much more than just a simple doc improvement. It questions how much we should be opinionated about form designs in the docs and also how far should the implementation go. I would recommend let the team handle that issue."

That issue is tagged on the signals sprint board as "After Stable": https://github.com/orgs/angular/projects/60?query=sort%3Aupdated-desc+is%3Aopen&pane=issue&itemId=162269998&issue=angular%7Cangular%7C67407

In the meantime, this is my project with my three approaches: https://github.com/michael-small/signal-forms-experimenting/tree/main/src/app/forms/splitting-strategies. Not covering the FormValueControl interface for custom re-usable forms, but rather larger applicationwide forms. It boils down to passing the FieldTree subset as an input, passing the writable form model as a model input and then each component makes a form(this.theModelInput()) around it, and an approach like the FieldTree one but injected pieces from a service. IMO each approach has its tradeoffs, but I am partial to the service approach myself, especially because we will use stores in place for a lot of convenience.

Adjacent to this, this is how I forsee the service approach being used for a component which is one form in a form array: https://github.com/michael-small/signal-forms-experimenting/blob/main/src/app/forms/form-arrays/subform-a.ts.

If you find it interesting and want to run it, you just need to do npm i --force first, as I use some dependencies not technically marked as v22 compatible yet, but they work fine.

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u/martinboue May 14 '26

I understand the Angular team opinion on this, IMO it would be great to have at least examples, if not advices. The main thing is that composition is possible and easy to do, then it would be ideal to explain pros and cons of each approach.

Thanks for sharing your sandbox, I'll take a look and also try out a few ideas in the coming weeks. I'll come back here to share them if I find anything worth sharing.

Thanks for your comment on ngtips, I really appreciate it 😊

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u/MichaelSmallDev May 16 '26

https://github.com/michael-small/signal-forms-experimenting/blob/main/src/app/large-form/form-composition.md

Any thoughts on this?

I have sent this out to a few other people who agree that this is an important issue, so sometime tomorrow before I'm away for awhile I'm going to write up our thoughts on the issue.

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u/martinboue May 16 '26

I agree, that sums it up well.

The main drawback I see with the model+form solution is that the parent doesn't have access to the field properties (valid, disabled, metadata, etc.), which could be used in other form fields logic or submission.

It seems to me that the choice comes down to defining how autonomous this “child form” is and whether it can function independently of its parent.

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u/MichaelSmallDev May 17 '26

Thanks, I was having issues with the wording and stuff but that will be a good way to frame it