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Create logic with JSON and store it in your backend

Expry is a JavaScript library for creating logic using JSON syntax. It enables you to store your code in your backend, making it ideal for use cases such as forms and validation rules.

const expression = {
name: { $concat: ["$name", " ", "$surname"] },
mostFavoriteSports: {
$filter: {
input: "$sports",
as: "sport",
cond: { $gt: ["$$sport.rating", 8] },
},
},
};
const variables = {
name: "Martí",
surname: "Serra",
sports: [
{ name: "football", rating: 9 },
{ name: "basketball", rating: 10 },
{ name: "tennis", rating: 5 },
{ name: "swimming", rating: 7 },
],
};
{
"name": "Martí Serra",
"mostFavoriteSports": [
{ "name": "football", "rating": 9 },
{ "name": "basketball", "rating": 10 }
]
}