# Session attributes changed
Learn how to track changes to session attributes.
This event tracks changes to session attributes.
> **Automatically tracked**
>
> We track this event for you, so no action is needed on your side.
## Implementation
Here is an example of how to track this event:
**JavaScript**
```javascript
import croct from '@croct/plug';
const patch = croct.session.edit();
const promise = patch
.set('selectedPlan', 'Premium')
.save();
```
**HTML**
```html
My awesome application
```
**React — JavaScript**
```jsx
import {useCroct} from '@croct/plug-react';
export function PlanCard({plan, price}) {
const croct = useCroct();
const onSelect = () => {
croct.session.edit()
.set('selectedPlan', plan)
.save();
};
return (
{plan}
${price}
);
}
```
**React — TypeScript**
```typescript
import type {ReactElement} from 'react';
import {useCroct} from '@croct/plug-react';
type PlanCardProps = {
plan: string,
price: number,
}
export function PlanCard({plan, price}: PlanCardProps): ReactElement {
const croct = useCroct();
const onSelect = (): void => {
croct.session.edit()
.set('selectedPlan', plan)
.save();
};
return (