# Optimistic comments
Source: https://signy.dev/examples/optimistic-comments/
Show the comment now, ask the server after.
A new comment goes into the resource with `mutate()` before the server answers, marked as pending. When the fake server fails, the comment is taken back out and a toast offers a retry.
## Preview
[Open the page on its own](https://signy.dev/examples/optimistic-comments/demo/index.html.md)
## Code
Save it as an `.html` file and open it in a browser. It loads Signy and Iris CSS from the CDN, so there is nothing to install or build.
**Show the full page**
```html
Optimistic comments - Signy example
```
## What it uses
- [Resource](https://signy.dev/documentation/1/reactivity/resource/index.html.md) with `mutate()` and `refetch()`
- [Portal](https://signy.dev/documentation/1/templates/portal-and-error-boundary/index.html.md) for the toast
- [For](https://signy.dev/documentation/1/templates/for-and-index/index.html.md) with `keyBy`