Code

Overview

The code node runs arbitrary JavaScript in a sandboxed V8 isolate, giving workflows the ability to transform data, compute values, or perform logic that no built-in node covers. The script receives the upstream input object as input and must return a value by assigning it to output. Network access, filesystem access, and native modules are not available inside the sandbox; for outbound calls use http_request instead. Only JavaScript is supported at this time.

Configuration

Field	Type	Required	Default	Description
code	string	Yes	—	The JavaScript source to execute. The variable input is pre-bound to the node's input object. Assign the result to output to pass data downstream.
language	string	No	"javascript"	Execution language. Currently only "javascript" is accepted.
timeout_ms	number	No	5000	Maximum milliseconds the script may run before it is forcibly terminated and the node fails.
memory_limit_mb	number	No	64	Maximum heap memory in megabytes the isolate may allocate. Exceeding this limit terminates the script.

Inputs

Port	Type	Description
input	any	Upstream data injected as the input variable inside the script.

Outputs

Port	Type	Description
output	any	The value assigned to the output variable inside the script. Can be any JSON-serialisable type.
error	object	Present when the script throws an unhandled exception or times out; contains message, stack, and code ("TIMEOUT" or "RUNTIME_ERROR").

Example

{
  "nodeType": "code",
  "config": {
    "language": "javascript",
    "timeout_ms": 3000,
    "memory_limit_mb": 32,
    "code": "const scores = input.contenders.map(c => c.score);\nconst winner = input.contenders.reduce((a, b) => a.score >= b.score ? a : b);\noutput = { winner: winner.id, max_score: Math.max(...scores), total: scores.length };"
  }
}

Notes

• The script must assign output before it exits; if output is never assigned, the node emits null and continues. No return statement is required at the top level.
• console.log() calls are captured and available in the workflow run logs for debugging; they do not appear in output.
• The sandbox has no access to fetch, require, process, or any Node.js built-in. Pure computation and JSON manipulation are the intended use cases.
• Scripts that mutate the input variable do not affect upstream nodes — input is a deep copy of the upstream output, not a reference.