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Environment Variables

Each session maintains its own set of environment variables, accessible to WASM programs via WASI environ_get / environ_sizes_get.

Set Environment Variables​

POST /api/v1/sessions/:id/env

Request body:

{
  "DATABASE_URL": "postgres://localhost/mydb",
  "DEBUG": "true"
}

Variables are merged — existing keys are updated, new keys are added.

Response (200):

{
  "message": "Set 2 environment variable(s)"
}

Get Environment Variables​

GET /api/v1/sessions/:id/env

Response (200):

{
  "env": {
    "DATABASE_URL": "postgres://localhost/mydb",
    "DEBUG": "true"
  }
}

Per-Execution Environment​

You can also set environment variables in the exec request. These are applied before execution and persist for subsequent calls:

POST /api/v1/sessions/:id/exec
{
  "wasm_path": "app.wasm",
  "env": {
    "MODE": "production"
  }
}