> ## Documentation Index
> Fetch the complete documentation index at: https://docs.squarecloud.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Environment variables

> List, add, replace and delete environment variables for an application.

`app.envs` exposes the [`EnvsModule`](https://github.com/squarecloudofc/sdk-api-js/blob/main/src/modules/envs.ts), which lets you manage the `KEY=value` pairs your application sees at runtime.

```typescript theme={null}
const app = await api.applications.fetch("abc123def456abc123def456");
app.envs; // EnvsModule
```

Every method resolves to the full env set after the operation completes — so you always get an up-to-date `{ key: value }` map back.

<Note>
  Limits: up to 256 variables per application, keys up to 1024 characters and values up to 4096 characters.
</Note>

## Listing environment variables

```typescript theme={null}
const envs = await app.envs.list();

console.log(envs);
// { DATABASE_URL: "postgres://...", FEATURE_FLAG: "true" }
```

## Adding or updating variables

`app.envs.set(envs)` merges new variables into the existing set. Existing keys not present in the call are preserved.

```typescript theme={null}
await app.envs.set({
    DATABASE_URL: "postgres://...",
    FEATURE_FLAG: "true",
});
```

## Replacing the entire env set

`app.envs.replace(envs)` overwrites every variable. Anything not listed is **removed**.

```typescript theme={null}
await app.envs.replace({
    DATABASE_URL: "postgres://new-host...",
});
// FEATURE_FLAG is now gone
```

Pass an empty object to wipe all variables:

```typescript theme={null}
await app.envs.replace({});
```

## Deleting variables

`app.envs.delete(keys)` removes the listed keys. Unknown keys are silently ignored.

```typescript theme={null}
await app.envs.delete(["FEATURE_FLAG"]);
```