JS Code on the canvas
Write JavaScript inline as a normal workflow step - same flow as any other node.
Extend workflows with custom JavaScript code
WEXTL® JS Code [1] node lets you write custom JavaScript directly on the visual workflow canvas [3] - between any of 1,300+ app integrations [2]. Reshape payloads, normalize responses, or strip PII before data reaches the next step. Curated modules like lodash, dayjs, zod, uuid come baked in [5] - no package.json or lockfile required.
WEXTL® runs your code in a secure V8 isolate with per-run limits [5]. Return values, console logs, and errors show on the run history [4] - just like every other native workflow node.
- GDPR
- Data Encryption
- 2FA
- Local Data Region
Video slide shows how JS Code node reshapes payloads on WEXTL® canvas.
Shape data for next app
Rename fields, transform payloads, and hand a clean object to the next connector.
Curated modules baked in
Import lodash, dayjs, zod, uuid, papaparse - no package.json, no lockfile to maintain.
Guardrails in JavaScript
Redact PII or reject bad rows before the next step fires - visible on run history.
How to add JS Code node into a workflow on WEXTL®?
There are only 3 main steps to plug a JS Code node [1] into your workflow. Under 5 minutes [5] setup - from picking where to insert it to a live JavaScript transform running in a V8 isolate between your apps.
STEP 1
Place JS Code node on canvas
Select and drop JS Code node inside the workflow where you expect it to work. Same drag and drop experience as any regular node [4] - no separate approach, right inside the workflow canvas [3].
STEP 2
Give it input, set the return shape
Reference upstream data using field mapping [1] and return the exact response next nodes expect. Plain JavaScript with curated modules - just like a regular node [5].
JS Code
// map form payload → CRM shapeconst form = input.nodes["webhook_1"];
return {
phone: form.cell_phone,
company: form.co ?? null,
};
STEP 3
Proceed based on JS code node output
Use a Condition or Merge nodes after to branch based on JS code node response. Output values and console logs stream to run history [4]. In case of any errors, JS node acts exactly as regular - no specific behavior.
How does JS Code integrates inside a WEXTL workflow?
JS Code [1] is just a regualr workflow node as 1,300+ others - same inputs and outputs connections, run history supported, same drag and drop experience you get with WEXTL native nodes.
Custom JS code can be placed in any part of the workflow - between two apps to convert their inputs and outputs, or before an app - to validate incomind data, or after - to normalize responses [5]. You can edit JavaScript code directly on the canvas [3] - no separate interface required.
Automator has access to a set of libraries to import in JS: lodash, dayjs, date-fns, zod, uuid, nanoid, papaparse, fast-xml-parser, jsonpath-plus, slugify [1]. This helps push JS code capabilities inside WEXTL even further.
Video shows JS Code settings inside workflow on WEXTL®.
Can built-in JS Code node handle failures and long-running tasks?
Each JS Code run has limit 300 seconds of execution time by default, and your plan [6] may set a different limit. This helps to avoid the situations when non intentional loop fails to exit and prevents the workflow automation from hanging for a long time.
Uncaught errors inside JS functions will mark the node as failed with the stack trace attached. Error handler can be used though, or Condition or Merge node after - can branch on failure to send a failure altert.
Any console.log, warn, and error calls inside function code will be streamed to the node results panel in the run viewer - builders see exactly what the transform decided, and why [4].
JS Code settings panel WEXTL®.
Supported integrations
Frequently asked questions
No. JS Code runs your own JavaScript in an isolate. The Function node is for built-in IML helpers, not user-authored code. This page is about JS Code.
Yes — a guarded fetch is available inside the isolate: SSRF-pinned (no localhost, private ranges, or metadata endpoints) and capped per run (request count, response bytes, and concurrency). For calls that need stored credentials, built-in retries, or rate-limit handling, the HTTP or an app node is still the better fit — hand JS Code the response to shape.
Yes. `async` / `await` is supported inside the isolate — use it for fetch, or any Promise-returning API. The node waits for the returned value before the next step in the workflow fires, so downstream nodes always see the resolved result rather than a pending promise.
Open the JS Code node in the builder and hit Test run — it executes your code against a sample input you provide (or the last real payload the upstream node produced) and shows the return value and any console output inline, without triggering any downstream app step.
Place JS Code before an agent to pre-shape context, or after one to normalize tool results, strip PII, or enforce a strict schema before the next action fires — the agent's output goes through the same isolate as any other payload.
Add JS Code where connectors fall short or explore more
References
List of resources used for writing this documentation page on WEXTL®. Follow a citation to jump straight to the source.
- WEXTL® JS Code node — custom JavaScript step node documentation.
- WEXTL® Apps Library — full catalog of supported app integrations.
- WEXTL® visual workflow builder — canvas for building and visually tracing automations.
- WEXTL® built-in workflow nodes — catalog of built-in nodes with per-node documentation pages.
- WEXTL® anonymized usage experience from customers — collected by support team and/or partners.
- WEXTL® pricing plans — per-plan entitlements — limits, quotas, and included features.